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-# Analyzing Logs of Large-Scale Software Systems using Time Curves Visualization
-
-This repository contains the supplementary data mentioned in the paper "Analyzing Logs
-of Large-Scale Software Systems using Time Curves Visualization". In addition, GIF animations
-of the static *Time Curves* in the paper are provided and can be played in your browser.
-
-## Table of contents
-
-1. [Animated Time Curves](#animated-time-curves)
- - [Spark Structured Streaming](#spark-structured-streaming)
- - [Apache Flink](#apache-flink)
- - [Kafka Streams](#kafka-streams)
- - [Zookeeper dataset](#zookeeper-dataset)
- - [Multiple curve analysis](#multiple-curve-analysis)
-2. [Logs source in each of the Stream Processing Frameworks](#logs-source-in-each-of-the-stream-processing-frameworks)
-3. [Example logs found in each stage of the Stream Processing Frameworks](#example-logs-found-in-each-stage-of-the-stream-processing-frameworks)
-4. [Grouping events in the Stream Processing Frameworks experiment](#grouping-events-in-the-stream-processing-frameworks-experiment)
-5. [Correlation of the Stream Processing Frameworks with throughput](#correlation-of-the-stream-processing-frameworks-with-throughput)
-6. [Hardware setup](#hardware-setup)
-7. [Counterexample that the proposed distance is not a metric](#counterexample-that-the-proposed-distance-is-not-a-metric)
-8. [Optimizations to the distance computation](#optimizations-to-the-distance-computation)
-9. [Representing time within Time Curves](#representing-time-within-time-curves)
-10. [Manual analysis of the Zookeeper log file](#manual-analysis-of-the-zookeeper-log-file)
-11. [Large Language Model summarization](#large-language-model-summarization)
- - [Query about single checkpoint summarization in Label C](#query-about-single-checkpoint-summarization-in-label-c)
- - [Query about single checkpoint summarization in Label D](#query-about-single-checkpoint-summarization-in-label-d)
- - [Query about pairwise comparison between checkpoints in Label D](#query-about-pairwise-comparison-between-checkpoints-in-label-d)
- - [Query about pairwise comparison between Label C and E](#query-about-pairwise-comparison-between-label-c-and-e)
-12. [Log datasets](#log-datasets)
-13. [Citing](#citing)
-14. [References](#references)
-
-## Animated Time Curves
-
-In this section, the animated versions of each of the presented Time
-Curve analysis are shown. Each curve begins fully drawn. Afterwards, it
-is played from start to end.
-
-### Spark Structured Streaming
-
-
-### Apache Flink
-
-
-### Kafka Streams
-
-
-### Zookeeper dataset
-
-
-### Multiple curve analysis
-
-
-## Logs source in each of the Stream Processing Frameworks
-
-The following sources were used for collection of logs in the Stream
-Processing frameworks, namely (1) the Spark driver for Spark Structured
-Streaming, (2) the consumer group worker that corresponds to the
-partition leader in Kafka Streams and (3) the job manager in Apache
-Flink.
-
-## Example logs found in each stage of the Stream Processing Frameworks
-
-The following table contains example logs that were found in each of the
-identified stages of interest in the stream processing framework
-analysis in Section IV-A. This includes startup, failure, recovery and
-shutdown.
-
-Note that for Kafka Streams there are no indistinguishable logs for the
-fault recovery besides what can be considered normal processing logging
-statements.
-```
-+-----------------+-----------------+-----------------+-----------------+
-| Stage | Spark Str. | Apache Flink | Kafka Streams |
-| | Streaming | | |
-+=================+=================+=================+=================+
-| Startup | INFO | INFO ... | INFO |
-| | SparkContext OS | RESOURCE PARAMS | AppInfoParser |
-| | info Linux 5 | ... logs jvm | Kafka version: |
-| | ... x86 64 | params | 3.5.0 |
-| | amd64 | Xmx1530082096 | |
-+-----------------+-----------------+-----------------+-----------------+
-| Failure | ERROR ... Lost | INFO ... | INFO ... |
-| | executor <*> | <*> switched | Revoked |
-| | Not receiving | from RUNNING to | partitions |
-| | heartbeat ... | FAILED on flink | |
-| | | ... | |
-+-----------------+-----------------+-----------------+-----------------+
-| Fault recovery | INFO ... | INFO ... | INFO Processed |
-| | Registered | Deploying | <*> total |
-| | | Source ... to | records |
-| | executor with | flink-taskmanag | |
-| | ID <*> | er | |
-| | | ... | |
-+-----------------+-----------------+-----------------+-----------------+
-| Shutdown | WARN ... | INFO ... | INFO Processed |
-| | Disconnected | Shutting down | <*> total |
-| | from Spark | remote daemon | records |
-| | cluster! ... | | |
-+-----------------+-----------------+-----------------+-----------------+
-```
-Table 1. Example of log records found in the stages corresponding to
-startup, failure injection, fault recovery and shutdown in the three
-different Stream Processing frameworks. Note that some messages have
-been reduced in size for clarity.
-
-## Grouping events in the Stream Processing Frameworks experiment
-
-This section includes additional details about the grouping of events
-given the set of parameters shown in Table 1. Parameters marked with `*`
-imply that they are *not* default.
-```
-+-----------------+-----------------+-----------------+-----------------+
-| | Spark Str. | Apache Flink | Kafka Streams |
-| | Stream. | | |
-+=================+=================+=================+=================+
-| Clustering | Drain, tree | Drain, tree | Drain, tree |
-| Algorithm | depth=8 | depth=8 | depth=8 |
-+-----------------+-----------------+-----------------+-----------------+
-| Clustering | 0.4 | 0.4 | 0.4 |
-| similarity | | | |
-+-----------------+-----------------+-----------------+-----------------+
-| Number of | Desired = 25, | Desired = 25, | Desired = 15*, |
-| checkpoints | resulted in 20 | resulted in 62 | resulted in 15 |
-+-----------------+-----------------+-----------------+-----------------+
-| Top k-gaps to | 10 | 10 | 10 |
-| use | | | |
-+-----------------+-----------------+-----------------+-----------------+
-| Relative window | 0.25 | 0.25 | 0.25 |
-| size | | | |
-+-----------------+-----------------+-----------------+-----------------+
-| Conv. Window | exp | exp | exp |
-+-----------------+-----------------+-----------------+-----------------+
-| Window thresh. | 1.01 | 1.01 | 1.01 |
-+-----------------+-----------------+-----------------+-----------------+
-| Min-max ratio | 0.05 | 0.05 | 0.001* |
-+-----------------+-----------------+-----------------+-----------------+
-```
-Table 2. Parameters used for the automatic grouping of events in the
-Stream Processing experiment.
-
-The following plots explain the grouping decisions for each framework.
-
-![](./media/image6.png)
-
-Figure 1. Grouping details in Spark Structured Streaming.
-
-In Spark Structured Streaming, the events align quite well with the
-injected failures. Notice that in some ocassions the split takes place
-because of either a severity change (which perfectly aligns with the
-injected failure) or as a result of a large time gap. Notice too that
-if the number of top k-gaps was reduced, the severity change would still
-group the events around the failures, however, currently the time gap
-event trigger occurs shortly before the severity level change, therefore
-instead of splitting into two different events, they are grouped into a
-single one. All event grouping parameters are left default for Spark.
-
-![](./media/image7.png)
-
-Figure 2. Grouping details in Apache Flink.
-
-In the case of Flink, we have many more events after every error because
-of the changes in severity level. This is not a problem because those
-checkpoints are almost identical and get put into halo clusters in the
-corresponding Time Curves. After the repetitive succession of errors, the next
-event is generated by the largest time gap, showing that the system is
-processing normally. All event grouping parameters are left default for Flink.
-
-![](./media/image8.png)
-
-Figure 3. Grouping details in Kafka Streams.
-
-The case of Kafka Streams is more complicated. As can be seen, up until the
-log number ~3,250, the reported severity level errors are not as a result of
-the injected failures. In fact, the failures are reported as standard `INFO`
-messages. This means that all the information corresponding to the failures is
-condensed exclusively into the last ~1,000 logs and therefore all the grouping
-occurs because of time gaps (between the 12 minute marks) rather than because of
-error messages or number of logs. This is the reason why the default grouping
-had to be changed from default, since no proper logging was available. As
-stated in the paper, this is partially due to the framework and the selection
-of the logging source (worker 0).
-
-## Correlation of the Stream Processing Frameworks with throughput
-
-This section shows how the throughput (in terms of messages processed
-per second) reported from the Stream Processing Frameworks correlates
-with the reported events of failure and recovery as reported in the main
-manuscript.
-
-![A graph of a graph Description automatically generated with medium
-confidence](./media/image9.png)
-
-Figure 4. Throughput measured as the number of processed records per
-second in each of the Stream Processing Frameworks.
-
-As can be seen in Figure 4, all frameworks exhibit a temporary decrease
-in throughput when the failures are injected (represented as vertical
-bars after every 12 minute mark). This aligns especially with the
-severity level changes and the time gaps observed in Spark Structured
-Streaming and Apache Flink. In the case of Kafka Streams, only the time
-gaps result in event splits due to the framework not reporting any
-severity change. These can be seen at the end of Figure 3, after the
-initial \~3,250 log records.
-
-## Hardware setup
-
-The scalability section of the manuscript was run on a local machine
-with an Intel Core i9-11950H with disabled turbo boost running at 2.60
-GHz and 64 GB of memory. They were run on WSL with Ubuntu version 22,
-Java 17 and Python 3.8.
-
-## Counterexample that the proposed distance is not a metric
-
-The following example proves that the checkpoint distance is not a
-metric (rather a semimetric) due to violating the triangle inequality.
-
-Let $x := {x_0, x_1, x_2, x_3, x_4, x_5, x_6, x_7} := A$, $y := {x_0, x_1}$, $z := {x_0, x_1, x_2, x_3}$, and the curve of 3 points $P := {x,y,z}$.
-
-Then $|A| = |x| = 8$ (8 unique templates, all are in $x$), $|y| = 2$, $|z| = 4$ and $|P| = 3$ (in total 3 points).
-
-Assume we have written down 24 different characters, and split them into templates $x_i$'s as follows:
-Put (concatenate in any order) first 9 characters into $x_2$, next 9 into $x_3$, each of the rest 6 characters into a separate template to get $|x_0|=|x_1|=|x_4|=|x_5|=|x_6|=|x_7|=1$. Now add the $x_1$ character to $x_2$ and $x_3$, so that $|x_2| = |x_3| = 10$, then:
-$d(x_2, x_1) = d(x_1, x_2) = d(x_1, x_3) = d(x_3, x_1) = \frac{1}{10}$
-and all other $d(x_i, x_j) = 1$. Moreover $x, y, z$ are nested:
-
-$y \subset z \subset x \implies D’(y,z) = D’(y,x) = D’(z,x) = 0.$
-
-$D’(x,y) = \frac{1}{8} \sum_{i=0}^{7} \min_{j = 0,1} d(x_i, y_j)$
-
-$= \frac{1}{8} (0 + 0 + \frac{1}{10} + \frac{1}{10} + 1 + 1 + 1 + 1) = \frac{21}{40},$
-
-$D’(x,z) = \frac{1}{8} \sum_{i=0}^{7} \min_{j = 0,1,2,3} d(x_i, z_j)$
-
-$= \frac{1}{8} (0 + 0 + 0 + 0 + 1 + 1 + 1 + 1) = \frac{1}{2},$
-
-$D’(z,y) = \frac{1}{4} \sum_{i=0}^{3} \min_{j = 0,1} d(z_i, y_j)$
-
-$= \frac{1}{4} (0 + 0 + \frac{1}{10} + \frac{1}{10}) = \frac{1}{20}.$
-
-$D(x,y) = \frac{\frac{21}{40}\log_2 8 + 0\log_2 2}{\log_2 (8 \cdot 2)} = \frac{63}{160} = 0.39375,$
-
-$D(x,z) = \frac{\frac{1}{2}\log_2 8 + 0\log_2 4}{\log_2 (8 \cdot 4)} = \frac{\frac{1}{2} \cdot 3}{5} = 0.3,$
-
-$D(z,y) = \frac{\frac{1}{20}\log_2 4 + 0\log_2 2}{\log_2 (4 \cdot 2)} = \frac{\frac{1}{20} \cdot 2}{3} = \frac{1}{30}.$
-
-We finally arrived at the violation of triangular inequality:
-$0.39375 = D(x,y) > D(x,z) + D(z,y) = \frac{3}{10} + \frac{1}{30} = \frac{1}{3}.$
-
-This concludes that $D(\cdot,\cdot)$ is not a metric, since it violates triangular inequality, but it is a semi-metric by definition.
-
-## Optimizations to the distance computation
-
-The proposed semimetric requires significant computation. It is
-comprised of multiple quadratic terms, including (1) the Levenshtein
-distance itself, which is quadratic in the length of the strings, (2)
-the comparison between two checkpoints is also quadratic, since it
-requires to compare all templates in one checkpoint to all templates in
-the other and finally (3) the comparison of all checkpoints, where a
-distance matrix between checkpoints is required for the projection, thus
-also resulting in a quadratic term. It can be seen that naively
-computing the distance aggregation can become unfeasible quickly.
-Therefore, a series of computational optimizations are used to lower the
-complexity of the approach.
-
-Let us first define the output of the aggregation of all distances,
-which is a symmetric matrix of pairwise distances between any two
-checkpoints noted as $D_{M} \in \mathbb{R}^{N \times N}$
-
-and defined entry-wise as follows:
-
-$$\forall i,j \in \{ 0,1,\ldots, \mid P \mid - 1\} D_{M}\lbrack i\rbrack\lbrack j\rbrack = D(P_{i},P_{j}).$$
-
-Given $D( \cdot , \cdot)$ is a normalized semimetric, we have that
-$D_{M} \in \lbrack 0,1\rbrack^{N \times N}$, is symmetric and its
-diagonal entries are all zeros, which implies that only strictly upper
-(or lower) triangular part of matrix needs to be calculated.
-
-The first measure is to pre-compute all pairwise distances between
-unique templates. This translates into avoiding recomputation overhead
-since there is a significant overlap of templates between checkpoints,
-thus resulting in the complexity being nearly independent from the
-number of checkpoints. To store distances between individual log
-templates, let us define a matrix and denote it
-$d_{M} \in (\lbrack 0,1\rbrack)^{\mid A \mid \times \mid A \mid}$, where
-$\forall i,j\, \in \{ 0,1,\ldots,\mid A\mid - 1 \}\, d_{M}\lbrack i \rbrack\lbrack j \rbrack = d( A_{i},A_{j})$.
-
-Clearly only strictly upper (or lower) triangular part of matrix needs
-to be computed explicitly since
-$d_{M}\lbrack i\rbrack\lbrack j\rbrack = d(A_{i},A_{j}) = d(A_{j},A_{i}) = d_{M}\lbrack j\rbrack\lbrack i\rbrack.$
-
-The second measure concerns the observation that many pairs of templates
-appear only on specific checkpoints. This is a natural consequence of
-the logging systems. Consider the example where an error appears only in
-a single checkpoint. Then it is likely that the error will produce a
-chain of log records related to it. When clustered, this will result in
-multiple templates being present only in this checkpoint, and therefore
-they cannot be compared together since checkpoints are compared only
-against other checkpoints and not themselves. For this purpose, the
-entries of $d_{M}$ are computed on demand, thus avoiding unnecessary
-comparisons as well.
-
-A third measure concerns the Levenshtein distance directly. It is
-possible to compute a lower bound for the Levenshtein distance based
-simply on length difference of the templates. If two templates
-significantly differ in length such estimate allows pruning further
-computation of $d(x_{i},y_{j})$ in case the lower bound is larger than
-the current minimum distance among pairs of templates with the current
-one, i.e., for fixed $x_{i}$ $d(x_{i},y_{j}) > \min d(x_{i},y_{j})$
-means that $d(x_{i},y_{j})$ will not change $D(x,y)$ due to min term in
-Eq. 1 and therefore can be skipped.
-
-In addition, in cases where there is a significant overlap between
-templates in checkpoints, it may be possible to replace most of the
-string comparisons by simple integer look-ups. This is achieved by
-extending each template with a unique identifier, in a similar fashion
-to hashing. However, hashing is not required since all templates are
-guaranteed to be unique due to the clustering approach. And only a fast
-identifier look-up is needed to check whether a given template is
-present in a checkpoint.
-
-Note that in total all these optimizations significantly lower the
-complexity of the average case without introducing any errors to
-$D_{M}$. Nevertheless, the worst-case scenario remains possible and for
-such cases the runtime can be further reduced by applying heuristic
-techniques which do in fact affect the result of $D_{M}$. Among others,
-this includes e.g., fine-tuning the clustering parameters to result in
-less templates, and in extreme cases, replacing the Levenshtein distance
-altogether by a faster approximation such as the Q-gram distance.
-
-## Representing time within Time Curves
-
-Representing time is necessary for understanding the sequence of events
-in a collection of logs. For visualizing the time dimension of the
-system evolution we follow another Gestalt Perception Principles
-\[1\] smooth curvature instead of straight lines to satisfy the
-Low of Continuity, which also helps to avoid confusions when the graph
-crosses itself (which is typical of recurrent processes), and color-time
-relation to utilize the Low of Similarity, which clarifies the direction
-of the evolution and allows to understand the flow of events in time on
-a static graph.
-
-In other words, time dimension in our Time Curves is represented in
-different, but complementary ways. First of all, checkpoints are
-connected in chronological order to form a continuous and smooth curve
-(achieved via using spline ideas, check the original paper for the
-details \[2\]). Secondly, color of the curve segments changes to
-highlight the evolution of the system states over time, i.e. specified
-color-scale correspond to relative time-scale, e.g. red to blue gradient
-correspond to start to end of the observation period. And last
-time-related feature is the thickness of the curve segments, which is
-increased proportionally to the ratio of time interval between the
-checkpoints and total time of observation.
-
-While for some processes having an order of events in time is already
-sufficient, for other observations estimates of interval between
-checkpoints is necessary to analyse the system\'s behaviour. Meaning
-that time relevance vary depending on the input. Therefore, *Time
-Curves* provide control of how much the timeline is folded, which allows
-users observe any state of the graph between curve-connected, purely
-similarity-based scatter plot and a timeline (similarity is completely
-ignored). We will refer to the process of transforming similarity
-projection into a timeline as \"unfolding in time\" or simply
-\"unfolding\" and it is performed via linear interpolation between point
-coordinates obtained from projection algorithm and from constructing a
-timeline, curvature is adjusted on the fly to preserve the smoothness
-between connective segments.
-
-## Manual analysis of the Zookeeper log file
-
-The following section shows the manual analysis of the roughly \~75,000
-logs contained in the Zookeeper dataset. Each row in Table 2 starts with
-a timestamp which corresponds to the timestamp of the first log line to
-which the description belongs to. The absolute number of logs included
-in the description follows. Note that the Zookeeper dataset needs to be
-sorted according to the timestamps in order to make sense. In addition,
-also note that the analysis is coarse-grained but also finer whenever
-new logs that did not appear before take place.
-```
-+-----------------------------------------------------------------------+
-| 2015-07-29 17:41:41,536 Logs 1 to 13 |
-| |
-| Startup process from Zookeeper, reading configuration, configuring |
-| quorum, data directory cleanup, quorum peer process starting (which |
-| is responsible for managing the zookeeper ensemble). |
-+=======================================================================+
-| 2015-07-29 17:41:41,692 Logs 14 to 44 |
-| |
-| Election leader process. The server binds the port. The server myid=1 |
-| enters the LOOKING state which means it is looking for a leader. The |
-| server proposes itself (0x0). It logs that there are connection |
-| issues to server 10.10.34.12 and 13. Finally receives a connection |
-| request from 10.10.34.12 showing that it is also on the looking |
-| state. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 17:42:28,519 Logs 45 to 63 |
-| |
-| Server transitions to the FOLLOWING state, meaning it found a Leader. |
-| The server logs configuration and so on. The election process is |
-| finished and notified its length. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 17:42:28,588 Logs 64 to 105 |
-| |
-| Before anything significant, another election process starts. The |
-| server myid=2 starts LOOKING and in the end it starts LEADING, thus |
-| replacing myid=1. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 17:42:30:418 Logs 106 to 203 |
-| |
-| Yet another election process starts with server myid=3 proposing |
-| itself, but there are connection problems, response notifications are |
-| taking very long. Server 2 becomes the new leader eventually. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 17:46:17,171 Logs 204 to 3,582 |
-| |
-| Connection requests from followers to the leaders occur with errors |
-| all the time (connection request, then connection broken, then |
-| interrupting, then some GOODBYES). These happen intertwined with |
-| "Unexpected exception causing shutdown while socket still open". |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:21:26,842 Logs 3,582 to 53,161 |
-| |
-| Connection requests are still failing but now without the unexpected |
-| exception. Simply being broken. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:37:24,535 Logs 53,162 to 53,206 |
-| |
-| Finally, connections from clients begin. Before it was all servers. |
-| Connections are established. New log files are created as well. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:37:27,211 Logs 53,206 to 53,218 |
-| |
-| Multiple errors from clients trying to create nodes which already |
-| exist (files). For example, "/home". |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:48:31,603 Logs 53,219 to 53,312 |
-| |
-| Connection requests from clients along with first-time ever properly |
-| closing sockets (and end of stream exceptions). |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:52:16,000 Logs 53,341 to 53,541 |
-| |
-| First ever messages of expiring sessions from clients because of |
-| timeout. Messages about the processed session termination follow. |
-| They get intertwined with standard client connection requests and |
-| established sessions. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:53:09,882 Logs 53,542 to 53,800 |
-| |
-| Follower has an exception and shuts down (server myid=3) (note that |
-| the leader is myid=2). It calls for shutdown and closes multiple |
-| connections of clients it had open. After it shuts down, it |
-| transitions to LOOKING to find the leader again. It also reads the |
-| snapshot to restore state. Multiple rounds of notifications take |
-| place for voting the new leader. Server myid=2 is the new leader. It |
-| was already leader, but since myid=3 had some problems, it triggered |
-| a new election. Meanwhile there are many client and server |
-| connections. |
-+-----------------------------------------------------------------------+
-| 2015-07-29 19:56:52,122 Logs 53,801 to 58,878 |
-| |
-| Standard sessions and connections are requested, established and |
-| finished (expiring and being closed as well). Some finish with the |
-| end of stream exception, but nothing significant. A node exists error |
-| is also there. |
-+-----------------------------------------------------------------------+
-| 2015-07-30 17:40:45,765 Logs 58,879 to 58,945 |
-| |
-| Connection is lost with myid=1 from myid=2 and myid=3. Therefore, a |
-| new election is triggered. The severs are on the LOOKING state. The |
-| "Have smaller server identified" log appears for the first time. The |
-| new leader is myid=1. |
-+-----------------------------------------------------------------------+
-| 2015-07-30 17:49:00,254 Logs 58,945 to 59,044 |
-| |
-| Normal processing. Another exception when following leader from |
-| myid=3. New election triggered. Meanwhile everything normal. |
-+-----------------------------------------------------------------------+
-| **\*All logs between 59,044 and 70,383\*** |
-| |
-| Now up until the end, multiple elections happen because there is |
-| always one server crashing every once in a while. Always intertwined |
-| with normal processing, but of less duration. Sometimes a new log |
-| file is also created -- this depends on epochs and so on. |
-+-----------------------------------------------------------------------+
-| 2015-08-24 15:26:54,671 Logs 70,383 to 73,993 |
-| |
-| After a lot of the previously described, a new election is initiated |
-| by myid=1, but this one is flawed. The server myid=1 is complaining |
-| for long about not being able to open a connection to myid=2 and |
-| myid=3. This lasts for long until finally elections are resolved and |
-| the new leader is myid=2. |
-+-----------------------------------------------------------------------+
-| 2015-08-25 08:03:15,876 Logs 73,993 to end (74,380) |
-| |
-| A couple elections more take place in a similar fashion, but no |
-| connection errors between servers. There is no shutdown or anything |
-| of similar nature at the end. |
-+-----------------------------------------------------------------------+
-```
-Snippet 1. Manual analysis of the Zookeeper log collection.
-
-## Large Language Model summarization
-
-In this section, a general Large Language Model (LLM) is used to further
-summarize and compare the logging information contained within
-checkpoints in the Time Curve analysis. While fine-tuning a custom Small
-Language Model is intended for future work, we show that a general LLM
-without any prior training or prompts is able to help with the
-summarization. This is the case due to these large models (such as GPT 4
-\[3\]) being trained on large corpus of text which typically
-include logs from the analysed datasets (e.g., Flink or Zookeeper).
-
-The interaction with Microsoft Copilot used for generating the answers
-in Section 4-B is recorded below. Quoted answers in the paper are
-highlighted in dark red.
-
-### Query about single checkpoint summarization in Label C
-```
-+-----------------------------------------------------------------------+
-| |
-| Can you summarize for me the following templates which correspond to |
-| logs from an apache zookeeper service? In particular, what is |
-| happening in the system? |
-| |
-| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
-| still open |
-| |
-| \- INFO \<\*\> - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> to \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
-| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
-| snapdir /var/lib/zookeeper/version-2 |
-| |
-| \- INFO \<\*\> - Creating new log file: \<\*\> |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
-| |
-| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
-| |
-| \- INFO \<\*\> - Have smaller server identifier, so dropping the |
-| connection: \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
-| |
-| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
-| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
-| (n.peerEPoch), \<\*\> (my state) |
-| |
-| \- INFO \<\*\> - Reading snapshot \<\*\> |
-| |
-| \- INFO \<\*\> - Received connection request \<\*\> |
-| |
-| \- INFO \<\*\> - Server environment:java.vendor=Oracle Corporation |
-| |
-| \- INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
-| built on 06/10/2013 17:26 GMT |
-| |
-| \- INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
-| \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - TCP NoDelay set to: true |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My election |
-| bind port: 0.0.0.0/0.0.0.0:3888 |
-| |
-| \- INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
-| scheduled. |
-| |
-| \- INFO \[main:QuorumPeerConfig\@101\] - Reading configuration from: |
-| /etc/zookeeper/conf/zoo.cfg |
-| |
-| \- INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
-| |
-| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
-| |
-| \- WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> error |
-| = |
-| |
-| \- WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
-| |
-| \- WARN \<\*\> - Interrupted while waiting for message on queue |
-| |
-| \- WARN \<\*\> - Interrupting SendWorker |
-| |
-| \- WARN \<\*\> - Send worker leaving thread |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o modeCopilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Certainly! Here's a summary of what is happening in the system based |
-| on the provided Apache ZooKeeper log templates: |
-| |
-| **Summary of Log Events** |
-| |
-| 1. **Unexpected Shutdown**: |
-| |
-| - ERROR \<\*\> - Unexpected exception causing shutdown while |
-| sock still open |
-| |
-| - An unexpected exception has caused the server to shut down |
-| while a socket was still open. |
-| |
-| 2. **Leader Election**: |
-| |
-| - INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
-| |
-| - The leader election process has taken place. |
-| |
-| 3. **Client Connections**: |
-| |
-| - INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at |
-| \<\*\> |
-| |
-| - A client is attempting to connect to the ZooKeeper server. |
-| |
-| - INFO \<\*\> - Closed socket connection for client \<\*\> |
-| which had sessionid \<\*\> |
-| |
-| - The server has closed a socket connection for a client, |
-| identified by a session ID. |
-| |
-| - INFO \<\*\> - Established session \<\*\> with negotiated |
-| timeout \<\*\> for client \<\*\> |
-| |
-| - A new session has been successfully established with a |
-| client, including a negotiated timeout. |
-| |
-| - INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFact |
-| ory\@197\] - |
-| Accepted socket connection from \<\*\> |
-| |
-| - The server has accepted a new socket connection from a |
-| client. |
-| |
-| 4. **Session Management**: |
-| |
-| - INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - |
-| Processed session termination for sessionid: \<\*\> |
-| |
-| - The server has processed the termination of a session, |
-| identified by a session ID. |
-| |
-| - INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring |
-| session \<\*\> timeout of \<\*\> exceeded |
-| |
-| - A session has expired because its timeout period was |
-| exceeded. |
-| |
-| 5. **Server Initialization and Configuration**: |
-| |
-| - INFO \<\*\> - Created server with tickTime 2000 |
-| minSessionTimeout 4000 maxSessionTimeout 40000 datadir |
-| /var/lib/zookeeper/version-2 snapdir |
-| /var/lib/zookeeper/version-2 |
-| |
-| - The server has been created with specific configuration |
-| parameters. |
-| |
-| - INFO \[main:QuorumPeerConfig\@101\] - Reading configuration |
-| from: /etc/zookeeper/conf/zoo.cfg |
-| |
-| - The server is reading its configuration from a specified |
-| file. |
-| |
-| - INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
-| |
-| - The quorum peer is starting. |
-| |
-| 6. **Synchronization and Data Management**: |
-| |
-| - INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
-| \<\*\> \<\*\> |
-| |
-| - The server is synchronizing with a follower. |
-| |
-| - INFO \<\*\> - Getting a diff from the leader \<\*\> |
-| |
-| - The server is getting a differential update from the leader. |
-| |
-| - INFO \<\*\> - Reading snapshot \<\*\> |
-| |
-| - The server is reading a snapshot. |
-| |
-| 7. **Warnings and Errors**: |
-| |
-| - WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> |
-| error = |
-| |
-| - A connection has been broken for a specific client ID. |
-| |
-| - WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@34 |
-| 9\] - |
-| caught end of stream exception |
-| |
-| - The server encountered an end-of-stream exception, indicating |
-| an unexpected disconnection. |
-| |
-| - WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@ |
-| 793\] - |
-| Connection request from old client \<\*\> will be dropped if |
-| server is in r-o mode |
-| |
-| - A connection request from an old client will be dropped if |
-| the server is in read-only mode. |
-| |
-| **Overall System Activity** |
-| |
-| The logs indicate that the ZooKeeper server is actively managing |
-| client connections and sessions, handling leader elections, |
-| initializing and configuring the server, and synchronizing data with |
-| followers. The server also deals with various warnings and errors, |
-| such as unexpected shutdowns, broken connections, and session |
-| expirations. |
-| |
-| Is there a specific part of this process you'd like to explore |
-| further? |
-| |
-| You |
-| |
-| **Sent by you:** |
-| |
-| Should I be worried about the errors? |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Errors in your ZooKeeper logs, especially those causing shutdowns, |
-| should definitely be investigated. Here are some steps to help you |
-| understand and address these errors: |
-| |
-| **Key Error to Address** |
-| |
-| - **Unexpected Exception Causing Shutdown**: |
-| |
-| - ERROR \<\*\> - Unexpected exception causing shutdown while |
-| sock still open |
-| |
-| - This indicates a critical issue that caused the server to |
-| shut down unexpectedly. It's important to identify the root |
-| cause to prevent future occurrences. |
-| |
-| **Potential Causes and Actions** |
-| |
-| 1. **Software Bugs**: |
-| |
-| - **Cause**: There might be a bug in the ZooKeeper software or |
-| your application. |
-| |
-| - **Action**: Check for any available updates or patches for |
-| ZooKeeper. Review recent changes in your application that |
-| might have introduced the issue. |
-| |
-| 2. **Resource Exhaustion**: |
-| |
-| - **Cause**: The server might be running out of resources |
-| (e.g., memory, CPU). |
-| |
-| - **Action**: Monitor resource usage on the server. Consider |
-| increasing resources or optimizing the application to use |
-| fewer resources. |
-| |
-| 3. **Network Issues**: |
-| |
-| - **Cause**: Network instability can cause unexpected |
-| disconnections and errors. |
-| |
-| - **Action**: Ensure that the network is stable and reliable. |
-| Check for any network configuration issues or hardware |
-| problems. |
-| |
-| 4. **Configuration Problems**: |
-| |
-| - **Cause**: Incorrect or suboptimal configuration settings can |
-| lead to errors. |
-| |
-| - **Action**: Review your ZooKeeper configuration settings. |
-| Ensure they are set according to best practices and your |
-| specific use case. |
-| |
-| **Monitoring and Prevention** |
-| |
-| - **Log Monitoring**: Continuously monitor your logs for errors and |
-| warnings. Set up alerts for critical issues. |
-| |
-| - **Regular Maintenance**: Perform regular maintenance tasks, such |
-| as cleaning up old data and ensuring the server is running |
-| optimally. |
-| |
-| - **Testing**: Test your application and ZooKeeper setup in a |
-| staging environment before deploying changes to production. |
-| |
-| **Conclusion** |
-| |
-| While occasional errors might not be a cause for immediate concern, |
-| frequent or critical errors like unexpected shutdowns should be |
-| addressed promptly to ensure the stability and reliability of your |
-| ZooKeeper service. |
-| |
-| Would you like more detailed guidance on any of these steps or have |
-| any specific concerns about your setup? |
-+-----------------------------------------------------------------------+
-```
-Snippet 2. Single checkpoint summarization in Label `C`.
-
-### Query about single checkpoint summarization in Label D
-```
-+-----------------------------------------------------------------------+
-| |
-| Can you summarize for me the following templates which correspond to |
-| logs from an apache zookeeper service? In particular, what is |
-| happening in the system? |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Certainly! Here's a summary of what is happening in the system based |
-| on the provided Apache ZooKeeper log templates: |
-| |
-| **Summary of Log Events** |
-| |
-| 1. **Client Connection Attempts**: |
-| |
-| - INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at |
-| \<\*\> |
-| |
-| - A client is trying to connect to the ZooKeeper server. |
-| |
-| 2. **Socket Connection Closure**: |
-| |
-| - INFO \<\*\> - Closed socket connection for client \<\*\> |
-| which had sessionid \<\*\> |
-| |
-| - The server has closed a socket connection for a client, |
-| identified by a session ID. |
-| |
-| 3. **Session Establishment**: |
-| |
-| - INFO \<\*\> - Established session \<\*\> with negotiated |
-| timeout \<\*\> for client \<\*\> |
-| |
-| - A new session has been successfully established with a |
-| client, including a negotiated timeout. |
-| |
-| 4. **Session Termination Processing**: |
-| |
-| - INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - |
-| Processed session termination for sessionid: \<\*\> |
-| |
-| - The server has processed the termination of a session, |
-| identified by a session ID. |
-| |
-| 5. **Socket Connection Acceptance**: |
-| |
-| - INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFact |
-| ory\@197\] - |
-| Accepted socket connection from \<\*\> |
-| |
-| - The server has accepted a new socket connection from a |
-| client. |
-| |
-| 6. **Session Expiration**: |
-| |
-| - INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring |
-| session \<\*\> timeout of \<\*\> exceeded |
-| |
-| - A session has expired because its timeout period was |
-| exceeded. |
-| |
-| 7. **End of Stream Exception**: |
-| |
-| - WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@34 |
-| 9\] - |
-| caught end of stream exception |
-| |
-| - The server encountered an end-of-stream exception, indicating |
-| an unexpected disconnection. |
-| |
-| 8. **Connection Request from Old Client**: |
-| |
-| - WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@ |
-| 793\] - |
-| Connection request from old client \<\*\> will be dropped if |
-| server is in r-o mode |
-| |
-| - A connection request from an old client will be dropped if |
-| the server is in read-only mode. |
-| |
-| **Overall System Activity** |
-| |
-| The logs indicate that the ZooKeeper server is actively managing |
-| client connections and sessions. It handles new connection attempts, |
-| establishes and terminates sessions, and processes session |
-| expirations. The server also deals with connection issues, such as |
-| end-of-stream exceptions and connection requests from outdated |
-| clients. |
-| |
-| Is there a specific part of this process you'd like to dive deeper |
-| into? |
-| |
-| You |
-| |
-| **Sent by you:** |
-| |
-| Should I be worried about the end-of-stream exceptions? |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| End-of-stream exceptions in ZooKeeper logs can indicate that a client |
-| connection was unexpectedly closed. While these exceptions are not |
-| uncommon and can occur for various reasons, they are worth |
-| monitoring. Here are a few considerations: |
-| |
-| **Potential Causes** |
-| |
-| 1. **Network Issues**: Temporary network disruptions can cause |
-| clients to disconnect unexpectedly. |
-| |
-| 2. **Client-Side Problems**: The client application might be |
-| experiencing issues or crashes. |
-| |
-| 3. **Server Overload**: The server might be under heavy load, |
-| causing it to drop connections. |
-| |
-| **Impact** |
-| |
-| - **Transient Issues**: If these exceptions are infrequent, they |
-| might not significantly impact the system. |
-| |
-| - **Persistent Problems**: Frequent end-of-stream exceptions could |
-| indicate underlying issues that need to be addressed, such as |
-| network instability or server performance problems. |
-| |
-| **Actions to Take** |
-| |
-| 1. **Monitor Frequency**: Keep an eye on how often these exceptions |
-| occur. A sudden increase might warrant further investigation. |
-| |
-| 2. **Check Network Stability**: Ensure that the network between |
-| clients and the server is stable and reliable. |
-| |
-| 3. **Review Client Logs**: Look at the client-side logs to see if |
-| there are any corresponding errors or issues. |
-| |
-| 4. **Server Performance**: Monitor the server's performance metrics |
-| to ensure it is not overloaded. |
-| |
-| If the end-of-stream exceptions are causing noticeable issues or if |
-| their frequency increases, it would be a good idea to investigate |
-| further to identify and resolve the root cause. |
-| |
-| Would you like more detailed steps on how to monitor and troubleshoot |
-| these exceptions? |
-+-----------------------------------------------------------------------+
-```
-Snippet 3. Single checkpoint summarization in Label `D`.
-
-### Query about pairwise comparison between checkpoints in Label D
-```
-+-----------------------------------------------------------------------+
-| |
-| Can you tell me the difference between these two set of logs? |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode |
-| |
-| And this other one: |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[ProcessThread(sid:2 cport:-1)::PrepRequestProcessor\@627\] |
-| - Got user-level KeeperException when processing \<\*\> type:create |
-| \<\*\> \<\*\> txntype:-1 reqpath:n/a Error \<\*\> |
-| Error:KeeperErrorCode = NodeExists for \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Certainly! Here are the differences between the two sets of logs: |
-| |
-| 1. **Additional INFO Log**: |
-| |
-| - **Second Set**: Contains an additional INFO log: |
-| |
-| - INFO \[ProcessThread(sid:2 |
-| cport:-1)::PrepRequestProcessor\@627\] - Got user-level |
-| KeeperException when processing \<\*\> type:create \<\*\> |
-| \<\*\> txntype:-1 reqpath:n/a Error \<\*\> |
-| Error:KeeperErrorCode = NodeExists for \<\*\> |
-| |
-| This log indicates a KeeperException due to a node already existing. |
-| |
-| 2. **Error Log Presence**: |
-| |
-| - **First Set**: Does not contain the KeeperException log |
-| mentioned above. |
-| |
-| These differences suggest that the second set of logs includes an |
-| additional event where a KeeperException occurred, indicating an |
-| attempt to create a node that already exists. |
-| |
-| Is there anything specific you need help with regarding these logs? |
-| |
-| You |
-| |
-| **Sent by you:** |
-| |
-| Is this \"KeeperException\" a serious error? |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| A KeeperException in ZooKeeper can vary in severity depending on the |
-| specific type of exception. The NodeExistsException, which is |
-| mentioned in your logs, indicates that an attempt was made to create |
-| a node that already exists. [This is generally not a critical error |
-| but rather an indication that the operation needs to handle the |
-| existence of the node more |
-| gracefully^1^](https://zookeeper.apache.org/doc/r3.3.3/api/org/apache |
-| /zookeeper/KeeperException.html). |
-| |
-| [However, other types of KeeperException can be more serious, such |
-| as ConnectionLossException or SessionExpiredException, which indicate |
-| issues with the connection to the ZooKeeper server or session |
-| management^1^](https://zookeeper.apache.org/doc/r3.3.3/api/org/apache |
-| /zookeeper/KeeperException.html). |
-| |
-| Would you like more details on handling specific types |
-| of KeeperException? |
-+-----------------------------------------------------------------------+
-```
-Snippet 4. Pairwise checkpoint summarization in Label `D`.
-
-### Query about pairwise comparison between Label C and E
-
-```
-+-----------------------------------------------------------------------+
-| |
-| Can you please tell me the similarities between these two sets of log |
-| lines from the Apache Zookeeper system? |
-| |
-| \- ERROR \<\*\> - Unexpected Exception: |
-| |
-| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
-| still open |
-| |
-| \- INFO \<\*\> - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> to \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
-| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
-| snapdir /var/lib/zookeeper/version-2 |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
-| |
-| \- INFO \<\*\> - Have smaller server identifier, so dropping the |
-| connection: \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
-| |
-| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
-| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
-| (n.peerEPoch), \<\*\> (my state) |
-| |
-| \- INFO \<\*\> - Reading snapshot \<\*\> |
-| |
-| \- INFO \<\*\> - Received connection request \<\*\> |
-| |
-| \- INFO \<\*\> - Server environment:java.vendor=Oracle Corporation |
-| |
-| \- INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
-| built on 06/10/2013 17:26 GMT |
-| |
-| \- INFO \<\*\> - TCP NoDelay set to: true |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My election |
-| bind port: 0.0.0.0/0.0.0.0:3888 |
-| |
-| \- INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
-| scheduled. |
-| |
-| \- INFO \[main:QuorumPeerConfig\@101\] - Reading configuration from: |
-| /etc/zookeeper/conf/zoo.cfg |
-| |
-| \- INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
-| |
-| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
-| |
-| \- WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> error |
-| = |
-| |
-| \- WARN \<\*\> - Interrupted while waiting for message on queue |
-| |
-| \- WARN \<\*\> - Interrupting SendWorker |
-| |
-| \- WARN \<\*\> - Send worker leaving thread |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode And this other one: |
-| |
-| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
-| still open |
-| |
-| \- INFO \<\*\> - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> exited loop! |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
-| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
-| snapdir /var/lib/zookeeper/version-2 |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
-| |
-| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
-| |
-| \- INFO \<\*\> - Have quorum of supporters starting up and setting |
-| last processed zxid: \<\*\> |
-| |
-| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
-| |
-| \- INFO \<\*\> - Notification time out: \<\*\> |
-| |
-| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
-| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
-| (n.peerEPoch), \<\*\> (my state) |
-| |
-| \- INFO \<\*\> - Reading snapshot \<\*\> |
-| |
-| \- INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
-| \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - shutdown of request processor complete |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@143\] - |
-| PrepRequestProcessor exited loop! |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner\@107\] - |
-| Revalidating client: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@1001\] - |
-| Closed socket connection for client \<\*\> (no session established |
-| for client) |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- INFO \[Thread-2:Leader\$LearnerCnxAcceptor\@309\] - exception |
-| while shutting down acceptor: java.net.SocketException: Socket closed |
-| |
-| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
-| |
-| \- WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
-| |
-| \- WARN \<\*\> - Exception when following the leader |
-| |
-| \- WARN \<\*\> - First is 0x0 |
-| |
-| \- WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@354\] - |
-| Exception causing close of session 0x0 due to java.io.IOException: |
-| ZooKeeperServer not running |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Certainly! Here are the similarities between the two sets of log |
-| lines from the Apache Zookeeper system: |
-| |
-| 1. **Log Levels**: Both sets include log lines with ERROR, INFO, |
-| and WARN levels, indicating different severities of events. |
-| |
-| 2. **Placeholders**: Both sets use placeholders (\<\*\>) to |
-| anonymize specific details such as session IDs, client IDs, or |
-| other dynamic values. |
-| |
-| 3. **Common Events**: |
-| |
-| - **Unexpected Exceptions**: Both sets have ERROR logs related |
-| to unexpected exceptions causing shutdowns. |
-| |
-| - **Leader Election**: Both sets include INFO logs about the |
-| leader election process. |
-| |
-| - **Socket Connections**: Both sets log information about |
-| socket connections being opened or closed. |
-| |
-| - **Session Management**: Both sets include logs about session |
-| creation, termination, and expiration. |
-| |
-| - **Snapshot Reading**: Both sets have logs related to reading |
-| snapshots. |
-| |
-| - **Client Requests**: Both sets log client connection requests |
-| and attempts. |
-| |
-| 4. **Server Environment**: Both sets include logs about the server |
-| environment and configuration details, such as Java vendor and |
-| Zookeeper version. |
-| |
-| 5. **Warnings**: Both sets contain WARN logs about connection |
-| issues, interruptions, and exceptions during operations. |
-| |
-| 6. **Specific Processes**: |
-| |
-| - **Leader Election Details**: Both sets provide detailed logs |
-| about the leader election process, including notifications |
-| and proposals. |
-| |
-| - **Session Handling**: Both sets log the establishment and |
-| termination of sessions, including details about session IDs |
-| and timeouts. |
-| |
-| - **Client Interactions**: Both sets include logs about client |
-| interactions, such as connection attempts and socket |
-| closures. |
-| |
-| These similarities indicate that both sets of logs are from the |
-| Apache Zookeeper system, capturing various operational events and |
-| issues related to leader election, session management, and client |
-| connections. |
-| |
-| You |
-| |
-| **Sent by you:** |
-| |
-| Could you please tell me what is the difference between these two |
-| sets of logs? |
-| |
-| \- ERROR \<\*\> - Unexpected Exception: |
-| |
-| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
-| still open |
-| |
-| \- INFO \<\*\> - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> to \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
-| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
-| snapdir /var/lib/zookeeper/version-2 |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
-| |
-| \- INFO \<\*\> - Have smaller server identifier, so dropping the |
-| connection: \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
-| |
-| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
-| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
-| (n.peerEPoch), \<\*\> (my state) |
-| |
-| \- INFO \<\*\> - Reading snapshot \<\*\> |
-| |
-| \- INFO \<\*\> - Received connection request \<\*\> |
-| |
-| \- INFO \<\*\> - Server environment:java.vendor=Oracle Corporation |
-| |
-| \- INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
-| built on 06/10/2013 17:26 GMT |
-| |
-| \- INFO \<\*\> - TCP NoDelay set to: true |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My election |
-| bind port: 0.0.0.0/0.0.0.0:3888 |
-| |
-| \- INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
-| scheduled. |
-| |
-| \- INFO \[main:QuorumPeerConfig\@101\] - Reading configuration from: |
-| /etc/zookeeper/conf/zoo.cfg |
-| |
-| \- INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
-| |
-| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
-| |
-| \- WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> error |
-| = |
-| |
-| \- WARN \<\*\> - Interrupted while waiting for message on queue |
-| |
-| \- WARN \<\*\> - Interrupting SendWorker |
-| |
-| \- WARN \<\*\> - Send worker leaving thread |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode And this other one: |
-| |
-| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
-| still open |
-| |
-| \- INFO \<\*\> - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
-| |
-| \- INFO \<\*\> - \<\*\> exited loop! |
-| |
-| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
-| |
-| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
-| sessionid \<\*\> |
-| |
-| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
-| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
-| snapdir /var/lib/zookeeper/version-2 |
-| |
-| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
-| \<\*\> for client \<\*\> |
-| |
-| \- INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
-| |
-| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
-| |
-| \- INFO \<\*\> - Have quorum of supporters starting up and setting |
-| last processed zxid: \<\*\> |
-| |
-| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
-| |
-| \- INFO \<\*\> - Notification time out: \<\*\> |
-| |
-| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
-| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
-| (n.peerEPoch), \<\*\> (my state) |
-| |
-| \- INFO \<\*\> - Reading snapshot \<\*\> |
-| |
-| \- INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
-| \<\*\> \<\*\> |
-| |
-| \- INFO \<\*\> - shutdown of request processor complete |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@143\] - |
-| PrepRequestProcessor exited loop! |
-| |
-| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
-| session termination for sessionid: \<\*\> |
-| |
-| \- INFO \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner\@107\] - |
-| Revalidating client: \<\*\> |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@1001\] - |
-| Closed socket connection for client \<\*\> (no session established |
-| for client) |
-| |
-| \- INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
-| \] |
-| - Accepted socket connection from \<\*\> |
-| |
-| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
-| \<\*\> timeout of \<\*\> exceeded |
-| |
-| \- INFO \[Thread-2:Leader\$LearnerCnxAcceptor\@309\] - exception |
-| while shutting down acceptor: java.net.SocketException: Socket closed |
-| |
-| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
-| |
-| \- WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
-| |
-| \- WARN \<\*\> - Exception when following the leader |
-| |
-| \- WARN \<\*\> - First is 0x0 |
-| |
-| \- WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
-| caught end of stream exception |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@354\] - |
-| Exception causing close of session 0x0 due to java.io.IOException: |
-| ZooKeeperServer not running |
-| |
-| \- WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Sure! Here are the differences between the two sets of logs: |
-| |
-| 1. **Error Logs**: |
-| |
-| - **First Set**: Contains two error logs: |
-| |
-| - ERROR \<\*\> - Unexpected Exception: |
-| |
-| - ERROR \<\*\> - Unexpected exception causing shutdown while |
-| sock still open |
-| |
-| - **Second Set**: Contains only one error log: |
-| |
-| - ERROR \<\*\> - Unexpected exception causing shutdown while |
-| sock still open |
-| |
-| 2. **INFO Logs**: |
-| |
-| - **First Set**: Includes the following INFO logs not present |
-| in the second set: |
-| |
-| - INFO \<\*\> - Have smaller server identifier, so dropping the |
-| connection: \<\*\> \<\*\> |
-| |
-| - INFO \<\*\> - Received connection request \<\*\> |
-| |
-| - INFO \<\*\> - Server environment:java.vendor=Oracle |
-| Corporation |
-| |
-| - INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
-| built on 06/10/2013 17:26 GMT |
-| |
-| - INFO \<\*\> - TCP NoDelay set to: true |
-| |
-| - INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My |
-| election bind port: 0.0.0.0/0.0.0.0:3888 |
-| |
-| - INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
-| scheduled. |
-| |
-| - INFO \[main:QuorumPeerConfig\@101\] - Reading configuration |
-| from: /etc/zookeeper/conf/zoo.cfg |
-| |
-| - INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
-| |
-| - **Second Set**: Includes the following INFO logs not present |
-| in the first set: |
-| |
-| - INFO \<\*\> - \<\*\> exited loop! |
-| |
-| - INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
-| |
-| - INFO \<\*\> - Have quorum of supporters starting up and |
-| setting last processed zxid: \<\*\> |
-| |
-| - INFO \<\*\> - Notification time out: \<\*\> |
-| |
-| - INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
-| \<\*\> \<\*\> |
-| |
-| - INFO \<\*\> - shutdown of request processor complete |
-| |
-| - INFO \<\*\> cport:-1)::PrepRequestProcessor\@143\] - |
-| PrepRequestProcessor exited loop! |
-| |
-| - INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner\@107\] - |
-| Revalidating client: \<\*\> |
-| |
-| - INFO |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@10 |
-| 01\] - |
-| Closed socket connection for client \<\*\> (no session |
-| established for client) |
-| |
-| - INFO \[Thread-2:Leader\$LearnerCnxAcceptor\@309\] - exception |
-| while shutting down acceptor: java.net.SocketException: |
-| Socket closed |
-| |
-| 3. **WARN Logs**: |
-| |
-| - **First Set**: Contains the following WARN logs not present |
-| in the second set: |
-| |
-| - WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> |
-| error = |
-| |
-| - WARN \<\*\> - Interrupted while waiting for message on queue |
-| |
-| - WARN \<\*\> - Interrupting SendWorker |
-| |
-| - WARN \<\*\> - Send worker leaving thread |
-| |
-| - **Second Set**: Contains the following WARN logs not present |
-| in the first set: |
-| |
-| - WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
-| |
-| - WARN \<\*\> - Exception when following the leader |
-| |
-| - WARN \<\*\> - First is 0x0 |
-| |
-| - WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
-| |
-| - WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@35 |
-| 4\] - |
-| Exception causing close of session 0x0 due to |
-| java.io.IOException: ZooKeeperServer not running |
-| |
-| These differences indicate that the first set of logs includes more |
-| detailed information about the server environment and configuration, |
-| while the second set includes more details about the election process |
-| and issues encountered during synchronization and session management. |
-| |
-| Is there anything specific you need help with regarding these logs? |
-| |
-| You |
-| |
-| **Sent by you:** |
-| |
-| Can you be more specific about the differences of WARN logs? What is |
-| changing betweem the two? |
-| |
-| Copilot |
-| |
-| **Sent by Copilot:** |
-| |
-| Certainly! Here are the specific differences in the WARN logs between |
-| the two sets: |
-| |
-| 1. **First Set**: |
-| |
-| - **Connection Issues**: |
-| |
-| - WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> |
-| error = |
-| |
-| - WARN \<\*\> - Interrupted while waiting for message on queue |
-| |
-| - WARN \<\*\> - Interrupting SendWorker |
-| |
-| - WARN \<\*\> - Send worker leaving thread |
-| |
-| These logs indicate issues with connection stability and |
-| interruptions in the message queue and send worker processes. |
-| |
-| 2. **Second Set**: |
-| |
-| - **Leader and Session Issues**: |
-| |
-| - WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
-| |
-| - WARN \<\*\> - Exception when following the leader |
-| |
-| - WARN \<\*\> - First is 0x0 |
-| |
-| - WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
-| |
-| - WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@35 |
-| 4\] - |
-| Exception causing close of session 0x0 due to |
-| java.io.IOException: ZooKeeperServer not running |
-| |
-| These logs highlight issues related to leader election and |
-| synchronization, such as unexpected zxid values and exceptions when |
-| following the leader, as well as a specific session closure due to |
-| the server not running. |
-| |
-| Both sets share some common WARN logs related to connection issues: |
-| |
-| WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
-| |
-| WARN \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] |
-| - caught end of stream exception |
-| |
-| WARN |
-| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
-| Connection request from old client \<\*\> will be dropped if server |
-| is in r-o mode |
-| |
-| These differences suggest that the first set focuses more on |
-| connection stability and worker interruptions, while the second set |
-| emphasizes leader election and synchronization issues. |
-| |
-| Is there anything else you need help with regarding these logs? |
-+-----------------------------------------------------------------------+
-```
-Snippet 5. Pairwise checkpoint summarization between Labels `C` and `D`.
-
-## Log datasets
-
-The following datasets were employed for each of the evaluation sections. These range in sizes from just a few thousand to four million logs.
-
-- Stream Processing analysis: The [Spark driver](data/spark-driver.log), [Flink job manager](data/flink-job-manager.log) and the [Kafka Streams worker #0](data/kafka-streams-worker-0.log) logs were used.
-- Public dataset analysis: The [Zookeeper](data/Zookeeper.log) log collection from LogPai [4] was used.
-- Multiple curve analysis: A proprietary dataset corresponding to three instances of the same application was used. This included stages such as application initialization, logger configuration, launching a Java server application, awaiting and servicing connections and also shutdown of the instance.
-- Scalability analysis: The HDFS, BGL, Spark and Windows log datasets were used from the [LogHub collection](https://zenodo.org/records/8196385). They were cropped to one million log lines in order to test the runtime as function of the variability.
-
-## Citing
-
-If you use our work, please cite the following paper:
-
-Borysenkov, Dmytro, Adriano Vogel, Sören Henning, and Esteban Perez-Wohlfeil. "Analyzing Logs of Large-Scale Software Systems Using Time Curves Visualization". arXiv [Cs.SE], 2024. arXiv. http://arxiv.org/abs/2411.05533.
-
-## References
-
-1. Koffka, Kurt. *Principles of Gestalt psychology*.
-routledge, 2013.
-
-2. Bach, Benjamin, Conglei Shi, Nicolas Heulot, Tara
-Madhyastha, Tom Grabowski, and Pierre Dragicevic. \"Time curves: Folding
-time to visualize patterns of temporal evolution in data.\" *IEEE
-transactions on visualization and computer graphics* 22, no. 1 (2015):
-559-568.
-
-3. Achiam, Josh, Steven Adler, Sandhini Agarwal, Lama Ahmad,
-Ilge Akkaya, Florencia Leoni Aleman, Diogo Almeida et al. \"Gpt-4
-technical report.\" *arXiv preprint arXiv:2303.08774* (2023).
-
-4. Zhu, Jieming, Shilin He, Pinjia He, Jinyang Liu, and Michael R. Lyu.
-"Loghub: A large collection of system log datasets for ai-driven log
-analytics." In 2023 IEEE 34th International Symposium on Software
-Reliability Engineering (ISSRE), pp. 355-366. IEEE, 2023.
+# Analyzing Logs of Large-Scale Software Systems using Time Curves Visualization
+
+This repository contains the supplementary data mentioned in the paper "Analyzing Logs
+of Large-Scale Software Systems using Time Curves Visualization". In addition, GIF animations
+of the static *Time Curves* in the paper are provided and can be played in your browser.
+
+## Table of contents
+
+1. [Animated Time Curves](#animated-time-curves)
+ - [Spark Structured Streaming](#spark-structured-streaming)
+ - [Apache Flink](#apache-flink)
+ - [Kafka Streams](#kafka-streams)
+ - [Zookeeper dataset](#zookeeper-dataset)
+ - [Multiple curve analysis](#multiple-curve-analysis)
+2. [Glossary](#glossary)
+3. [Logs source in each of the Stream Processing Frameworks](#logs-source-in-each-of-the-stream-processing-frameworks)
+4. [Example logs found in each stage of the Stream Processing Frameworks](#example-logs-found-in-each-stage-of-the-stream-processing-frameworks)
+5. [Grouping events in the Stream Processing Frameworks experiment](#grouping-events-in-the-stream-processing-frameworks-experiment)
+6. [Correlation of the Stream Processing Frameworks with throughput](#correlation-of-the-stream-processing-frameworks-with-throughput)
+7. [Hardware setup](#hardware-setup)
+8. [Proofs for the distance function being a semimetric](#proofs-for-the-distance-function-being-a-semimetric)
+9. [Counterexample that the proposed distance is not a metric](#counterexample-that-the-proposed-distance-is-not-a-metric)
+10. [Optimizations to the distance computation](#optimizations-to-the-distance-computation)
+11. [Representing time within Time Curves](#representing-time-within-time-curves)
+12. [Manual analysis of the Zookeeper log file](#manual-analysis-of-the-zookeeper-log-file)
+13. [Large Language Model summarization](#large-language-model-summarization)
+ - [Query about single checkpoint summarization in Label C](#query-about-single-checkpoint-summarization-in-label-c)
+ - [Query about single checkpoint summarization in Label D](#query-about-single-checkpoint-summarization-in-label-d)
+ - [Query about pairwise comparison between checkpoints in Label D](#query-about-pairwise-comparison-between-checkpoints-in-label-d)
+ - [Query about pairwise comparison between Label C and E](#query-about-pairwise-comparison-between-label-c-and-e)
+14. [Log datasets](#log-datasets)
+15. [Citing](#citing)
+16. [References](#references)
+
+## Animated Time Curves
+
+In this section, the animated versions of each of the presented Time
+Curve analysis are shown. Each curve begins fully drawn. Afterwards, it
+is played from start to end.
+
+### Spark Structured Streaming
+
+
+### Apache Flink
+
+
+### Kafka Streams
+
+
+### Zookeeper dataset
+
+
+### Multiple curve analysis
+
+
+## Glossary
+
+The following terms are used throughout the main manuscript. Definitions are provided
+in the context used in the manuscript, rather than their formal definitions.
+
+- Log: String represented text message usually consisting of a timestamp and a payload.
+- Template: A string representation of a set of logs which are very close semantically and typically differ only in syntactical elements, such as host names or service ID's.
+- Distance: A number that quantifies how far away two objects are, such as for example, points in a 2D projection. Similarly, the notion of distance may be extended to be a "metric distance", where formal mathematical constraints must be satisfied (e.g. triangle inequality).
+- Semimetric: A semimetric is a distance metric that does not satisfy the triangle inequality but does satisfy all other constraints (separation, positivity, symmetry).
+- Similarity measure: Inversely to a distance, it quantifies how close two objects are.
+- Time Curve: A 2D projection of a set of data points which includes information about time and similarity between them.
+- System: Any computer machine that can provide logging or tracing about the execution that is being performed.
+- Event: A set of consecutive logs of a system which are related by, e.g., process, cause, etc.; in other words, a snapshot over small timeframe of a system based on the logging.
+- Checkpoint: Representation of an event, which keeps its timestamp and corresponds to a data point in a Time Curve but replaces the set of original logs with a set of templates.
+- Evolution of the system: Chronological sequence of events representing changes in the behavior of the system over time.
+- Pattern: A set of contiguous checkpoints visually representing a particular evolution of the system, such as cycles, clusters, etc.
+
+Example visual patterns of interest in Time Curves can be found below:
+
+
+
+## Logs source in each of the Stream Processing Frameworks
+
+The following sources were used for collection of logs in the Stream
+Processing frameworks, namely (1) the Spark driver for Spark Structured
+Streaming, (2) the consumer group worker that corresponds to the
+partition leader in Kafka Streams and (3) the job manager in Apache
+Flink.
+
+## Example logs found in each stage of the Stream Processing Frameworks
+
+The following table contains example logs that were found in each of the
+identified stages of interest in the stream processing framework
+analysis in Section IV-A. This includes startup, failure, recovery and
+shutdown.
+
+Note that for Kafka Streams there are no indistinguishable logs for the
+fault recovery besides what can be considered normal processing logging
+statements.
+```
++-----------------+-----------------+-----------------+-----------------+
+| Stage | Spark Str. | Apache Flink | Kafka Streams |
+| | Streaming | | |
++=================+=================+=================+=================+
+| Startup | INFO | INFO ... | INFO |
+| | SparkContext OS | RESOURCE PARAMS | AppInfoParser |
+| | info Linux 5 | ... logs jvm | Kafka version: |
+| | ... x86 64 | params | 3.5.0 |
+| | amd64 | Xmx1530082096 | |
++-----------------+-----------------+-----------------+-----------------+
+| Failure | ERROR ... Lost | INFO ... | INFO ... |
+| | executor <*> | <*> switched | Revoked |
+| | Not receiving | from RUNNING to | partitions |
+| | heartbeat ... | FAILED on flink | |
+| | | ... | |
++-----------------+-----------------+-----------------+-----------------+
+| Fault recovery | INFO ... | INFO ... | INFO Processed |
+| | Registered | Deploying | <*> total |
+| | | Source ... to | records |
+| | executor with | flink-taskmanag | |
+| | ID <*> | er | |
+| | | ... | |
++-----------------+-----------------+-----------------+-----------------+
+| Shutdown | WARN ... | INFO ... | INFO Processed |
+| | Disconnected | Shutting down | <*> total |
+| | from Spark | remote daemon | records |
+| | cluster! ... | | |
++-----------------+-----------------+-----------------+-----------------+
+```
+Table 1. Example of log records found in the stages corresponding to
+startup, failure injection, fault recovery and shutdown in the three
+different Stream Processing frameworks. Note that some messages have
+been reduced in size for clarity.
+
+## Grouping events in the Stream Processing Frameworks experiment
+
+This section includes additional details about the grouping of events
+given the set of parameters shown in Table 1. Parameters marked with `*`
+imply that they are *not* default.
+```
++-----------------+-----------------+-----------------+-----------------+
+| | Spark Str. | Apache Flink | Kafka Streams |
+| | Stream. | | |
++=================+=================+=================+=================+
+| Clustering | Drain, tree | Drain, tree | Drain, tree |
+| Algorithm | depth=8 | depth=8 | depth=8 |
++-----------------+-----------------+-----------------+-----------------+
+| Clustering | 0.4 | 0.4 | 0.4 |
+| similarity | | | |
++-----------------+-----------------+-----------------+-----------------+
+| Number of | Desired = 25, | Desired = 25, | Desired = 15*, |
+| checkpoints | resulted in 20 | resulted in 62 | resulted in 15 |
++-----------------+-----------------+-----------------+-----------------+
+| Top k-gaps to | 10 | 10 | 10 |
+| use | | | |
++-----------------+-----------------+-----------------+-----------------+
+| Relative window | 0.25 | 0.25 | 0.25 |
+| size | | | |
++-----------------+-----------------+-----------------+-----------------+
+| Conv. Window | exp | exp | exp |
++-----------------+-----------------+-----------------+-----------------+
+| Window thresh. | 1.01 | 1.01 | 1.01 |
++-----------------+-----------------+-----------------+-----------------+
+| Min-max ratio | 0.05 | 0.05 | 0.001* |
++-----------------+-----------------+-----------------+-----------------+
+```
+Table 2. Parameters used for the automatic grouping of events in the
+Stream Processing experiment.
+
+The following plots explain the grouping decisions for each framework.
+
+![](./media/image6.png)
+
+Figure 1. Grouping details in Spark Structured Streaming.
+
+In Spark Structured Streaming, the events align quite well with the
+injected failures. Notice that in some ocassions the split takes place
+because of either a severity change (which perfectly aligns with the
+injected failure) or as a result of a large time gap. Notice too that
+if the number of top k-gaps was reduced, the severity change would still
+group the events around the failures, however, currently the time gap
+event trigger occurs shortly before the severity level change, therefore
+instead of splitting into two different events, they are grouped into a
+single one. All event grouping parameters are left default for Spark.
+
+![](./media/image7.png)
+
+Figure 2. Grouping details in Apache Flink.
+
+In the case of Flink, we have many more events after every error because
+of the changes in severity level. This is not a problem because those
+checkpoints are almost identical and get put into halo clusters in the
+corresponding Time Curves. After the repetitive succession of errors, the next
+event is generated by the largest time gap, showing that the system is
+processing normally. All event grouping parameters are left default for Flink.
+
+![](./media/image8.png)
+
+Figure 3. Grouping details in Kafka Streams.
+
+The case of Kafka Streams is more complicated. As can be seen, up until the
+log number ~3,250, the reported severity level errors are not as a result of
+the injected failures. In fact, the failures are reported as standard `INFO`
+messages. This means that all the information corresponding to the failures is
+condensed exclusively into the last ~1,000 logs and therefore all the grouping
+occurs because of time gaps (between the 12 minute marks) rather than because of
+error messages or number of logs. This is the reason why the default grouping
+had to be changed from default, since no proper logging was available. As
+stated in the paper, this is partially due to the framework and the selection
+of the logging source (worker 0).
+
+## Correlation of the Stream Processing Frameworks with throughput
+
+This section shows how the throughput (in terms of messages processed
+per second) reported from the Stream Processing Frameworks correlates
+with the reported events of failure and recovery as reported in the main
+manuscript.
+
+![A graph of a graph Description automatically generated with medium
+confidence](./media/image9.png)
+
+Figure 4. Throughput measured as the number of processed records per
+second in each of the Stream Processing Frameworks.
+
+As can be seen in Figure 4, all frameworks exhibit a temporary decrease
+in throughput when the failures are injected (represented as vertical
+bars after every 12 minute mark). This aligns especially with the
+severity level changes and the time gaps observed in Spark Structured
+Streaming and Apache Flink. In the case of Kafka Streams, only the time
+gaps result in event splits due to the framework not reporting any
+severity change. These can be seen at the end of Figure 3, after the
+initial \~3,250 log records.
+
+## Hardware setup
+
+The scalability section of the manuscript was run on a local machine
+with an Intel Core i9-11950H with disabled turbo boost running at 2.60
+GHz and 64 GB of memory. They were run on WSL with Ubuntu version 22,
+Java 17 and Python 3.8.
+
+## Proofs for the distance function being a semimetric
+The proposed distance function is formally not a metric, since a metric needs to satisfy the following properties for any elements $x$ and $y$ from the set:
+1. **Non-negativity**: $dist(x, y) \geq 0$.
+2. **Identity of indiscernibles**: $dist(x, y) = 0 \iff x = y$.
+3. **Symmetry**: $dist(x, y) = dist(y, x)$.
+4. **Triangle inequality**: $dist(x, z) \leq dist(x, y) + dist(y, z)$.
+
+If only the first 3 properties are satisfied, but the triangular inequality
+is violated, then $dist$ is a semimetric. We will now prove that $D(\cdot,\cdot)$ is indeed a semimetric over the set of all possible checkpoints.
+
+1. Since all terms are non-negative, so is the $D(\cdot, \cdot)$, *i.e.*:
+ $$D'(x,y) = \frac{1}{m} \sum_{i=0}^{m} \min_{j} d(y_i, x_j) \overset{d(x_i,y_j) \geq 0}{\geq} 0.$$
+ $$D(x,y) {\geq} \frac{\log_2 |x| \cdot 0 + \log_2 |y| \cdot 0}{\log_2 |x| + \log_2 |y|} = 0.$$
+
+2. Identity of indiscernibles can be verified as follows:
+ $$\begin{align*}
+ D(x,y) = 0 &\iff D'(x,y) = D'(y,x) = 0 \\
+ &\iff \left\{
+ \begin{array}{ll}
+ \forall i \min_{j = 0,\dots, n-1} &d(x_i, y_j) = 0, \\
+ \forall j \min_{i = 0,\dots, m-1} &d(y_j, x_i) = 0. \\
+ \end{array} \right. \\
+ &\iff \forall i \ \ x_i \in y \text{ and } \forall j \ \ y_j \in x \\
+ &\iff x \subseteq y \text{ and } y \subseteq x \\
+ &\iff x = y.
+ \end{align*} $$
+3. Symmetry holds by design, because $D(x,y)$ involves both $D'(x,y)$ and $D'(y,x)$.
+4. The triangular inequality is the only violation of metric properties. This can be seen with nested checkpoints (a counterexample is available in section [Counterexample that the proposed distance is not a metric](#counterexample-that-the-proposed-distance-is-not-a-metric) ).
+
+## Counterexample that the proposed distance is not a metric
+
+The following example proves that the checkpoint distance is not a
+metric (rather a semimetric) due to violating the triangle inequality.
+
+Let $x := {x_0, x_1, x_2, x_3, x_4, x_5, x_6, x_7} := A$, $y := {x_0, x_1}$, $z := {x_0, x_1, x_2, x_3}$, and the curve of 3 points $P := {x,y,z}$.
+
+Then $|A| = |x| = 8$ (8 unique templates, all are in $x$), $|y| = 2$, $|z| = 4$ and $|P| = 3$ (in total 3 points).
+
+Assume we have written down 24 different characters, and split them into templates $x_i$'s as follows:
+Put (concatenate in any order) first 9 characters into $x_2$, next 9 into $x_3$, each of the rest 6 characters into a separate template to get $|x_0|=|x_1|=|x_4|=|x_5|=|x_6|=|x_7|=1$. Now add the $x_1$ character to $x_2$ and $x_3$, so that $|x_2| = |x_3| = 10$, then:
+$d(x_2, x_1) = d(x_1, x_2) = d(x_1, x_3) = d(x_3, x_1) = \frac{1}{10}$
+and all other $d(x_i, x_j) = 1$. Moreover $x, y, z$ are nested:
+
+$y \subset z \subset x \implies D’(y,z) = D’(y,x) = D’(z,x) = 0.$
+
+$D’(x,y) = \frac{1}{8} \sum_{i=0}^{7} \min_{j = 0,1} d(x_i, y_j)$
+
+$= \frac{1}{8} (0 + 0 + \frac{1}{10} + \frac{1}{10} + 1 + 1 + 1 + 1) = \frac{21}{40},$
+
+$D’(x,z) = \frac{1}{8} \sum_{i=0}^{7} \min_{j = 0,1,2,3} d(x_i, z_j)$
+
+$= \frac{1}{8} (0 + 0 + 0 + 0 + 1 + 1 + 1 + 1) = \frac{1}{2},$
+
+$D’(z,y) = \frac{1}{4} \sum_{i=0}^{3} \min_{j = 0,1} d(z_i, y_j)$
+
+$= \frac{1}{4} (0 + 0 + \frac{1}{10} + \frac{1}{10}) = \frac{1}{20}.$
+
+$D(x,y) = \frac{\frac{21}{40}\log_2 8 + 0\log_2 2}{\log_2 (8 \cdot 2)} = \frac{63}{160} = 0.39375,$
+
+$D(x,z) = \frac{\frac{1}{2}\log_2 8 + 0\log_2 4}{\log_2 (8 \cdot 4)} = \frac{\frac{1}{2} \cdot 3}{5} = 0.3,$
+
+$D(z,y) = \frac{\frac{1}{20}\log_2 4 + 0\log_2 2}{\log_2 (4 \cdot 2)} = \frac{\frac{1}{20} \cdot 2}{3} = \frac{1}{30}.$
+
+We finally arrived at the violation of triangular inequality:
+$0.39375 = D(x,y) > D(x,z) + D(z,y) = \frac{3}{10} + \frac{1}{30} = \frac{1}{3}.$
+
+This concludes that $D(\cdot,\cdot)$ is not a metric, since it violates triangular inequality, but it is a semi-metric by definition.
+
+## Optimizations to the distance computation
+
+The proposed semimetric requires significant computation. It is
+comprised of multiple quadratic terms, including (1) the Levenshtein
+distance itself, which is quadratic in the length of the strings, (2)
+the comparison between two checkpoints is also quadratic, since it
+requires to compare all templates in one checkpoint to all templates in
+the other and finally (3) the comparison of all checkpoints, where a
+distance matrix between checkpoints is required for the projection, thus
+also resulting in a quadratic term. It can be seen that naively
+computing the distance aggregation can become unfeasible quickly.
+Therefore, a series of computational optimizations are used to lower the
+complexity of the approach.
+
+Let us first define the output of the aggregation of all distances,
+which is a symmetric matrix of pairwise distances between any two
+checkpoints noted as $D_{M} \in \mathbb{R}^{N \times N}$
+
+and defined entry-wise as follows:
+
+$$\forall i,j \in \{ 0,1,\ldots, \mid P \mid - 1\} D_{M}\lbrack i\rbrack\lbrack j\rbrack = D(P_{i},P_{j}).$$
+
+Given $D( \cdot , \cdot)$ is a normalized semimetric, we have that
+$D_{M} \in \lbrack 0,1\rbrack^{N \times N}$, is symmetric and its
+diagonal entries are all zeros, which implies that only strictly upper
+(or lower) triangular part of matrix needs to be calculated.
+
+The first measure is to pre-compute all pairwise distances between
+unique templates. This translates into avoiding recomputation overhead
+since there is a significant overlap of templates between checkpoints,
+thus resulting in the complexity being nearly independent from the
+number of checkpoints. To store distances between individual log
+templates, let us define a matrix and denote it
+$d_{M} \in (\lbrack 0,1\rbrack)^{\mid A \mid \times \mid A \mid}$, where
+$\forall i,j\, \in \{ 0,1,\ldots,\mid A\mid - 1 \}\, d_{M}\lbrack i \rbrack\lbrack j \rbrack = d( A_{i},A_{j})$.
+
+Clearly only strictly upper (or lower) triangular part of matrix needs
+to be computed explicitly since
+$d_{M}\lbrack i\rbrack\lbrack j\rbrack = d(A_{i},A_{j}) = d(A_{j},A_{i}) = d_{M}\lbrack j\rbrack\lbrack i\rbrack.$
+
+The second measure concerns the observation that many pairs of templates
+appear only on specific checkpoints. This is a natural consequence of
+the logging systems. Consider the example where an error appears only in
+a single checkpoint. Then it is likely that the error will produce a
+chain of log records related to it. When clustered, this will result in
+multiple templates being present only in this checkpoint, and therefore
+they cannot be compared together since checkpoints are compared only
+against other checkpoints and not themselves. For this purpose, the
+entries of $d_{M}$ are computed on demand, thus avoiding unnecessary
+comparisons as well.
+
+A third measure concerns the Levenshtein distance directly. It is
+possible to compute a lower bound for the Levenshtein distance based
+simply on length difference of the templates. If two templates
+significantly differ in length such estimate allows pruning further
+computation of $d(x_{i},y_{j})$ in case the lower bound is larger than
+the current minimum distance among pairs of templates with the current
+one, i.e., for fixed $x_{i}$ $d(x_{i},y_{j}) > \min d(x_{i},y_{j})$
+means that $d(x_{i},y_{j})$ will not change $D(x,y)$ due to min term in
+Eq. 1 and therefore can be skipped.
+
+In addition, in cases where there is a significant overlap between
+templates in checkpoints, it may be possible to replace most of the
+string comparisons by simple integer look-ups. This is achieved by
+extending each template with a unique identifier, in a similar fashion
+to hashing. However, hashing is not required since all templates are
+guaranteed to be unique due to the clustering approach. And only a fast
+identifier look-up is needed to check whether a given template is
+present in a checkpoint.
+
+Note that in total all these optimizations significantly lower the
+complexity of the average case without introducing any errors to
+$D_{M}$. Nevertheless, the worst-case scenario remains possible and for
+such cases the runtime can be further reduced by applying heuristic
+techniques which do in fact affect the result of $D_{M}$. Among others,
+this includes e.g., fine-tuning the clustering parameters to result in
+less templates, and in extreme cases, replacing the Levenshtein distance
+altogether by a faster approximation such as the Q-gram distance.
+
+## Representing time within Time Curves
+
+Representing time is necessary for understanding the sequence of events
+in a collection of logs. For visualizing the time dimension of the
+system evolution we follow another Gestalt Perception Principles
+\[1\] smooth curvature instead of straight lines to satisfy the
+Low of Continuity, which also helps to avoid confusions when the graph
+crosses itself (which is typical of recurrent processes), and color-time
+relation to utilize the Low of Similarity, which clarifies the direction
+of the evolution and allows to understand the flow of events in time on
+a static graph.
+
+In other words, time dimension in our Time Curves is represented in
+different, but complementary ways. First of all, checkpoints are
+connected in chronological order to form a continuous and smooth curve
+(achieved via using spline ideas, check the original paper for the
+details \[2\]). Secondly, color of the curve segments changes to
+highlight the evolution of the system states over time, i.e. specified
+color-scale correspond to relative time-scale, e.g. red to blue gradient
+correspond to start to end of the observation period. And last
+time-related feature is the thickness of the curve segments, which is
+increased proportionally to the ratio of time interval between the
+checkpoints and total time of observation.
+
+While for some processes having an order of events in time is already
+sufficient, for other observations estimates of interval between
+checkpoints is necessary to analyse the system\'s behaviour. Meaning
+that time relevance vary depending on the input. Therefore, *Time
+Curves* provide control of how much the timeline is folded, which allows
+users observe any state of the graph between curve-connected, purely
+similarity-based scatter plot and a timeline (similarity is completely
+ignored). We will refer to the process of transforming similarity
+projection into a timeline as \"unfolding in time\" or simply
+\"unfolding\" and it is performed via linear interpolation between point
+coordinates obtained from projection algorithm and from constructing a
+timeline, curvature is adjusted on the fly to preserve the smoothness
+between connective segments.
+
+## Manual analysis of the Zookeeper log file
+
+The following section shows the manual analysis of the roughly \~75,000
+logs contained in the Zookeeper dataset. Each row in Table 2 starts with
+a timestamp which corresponds to the timestamp of the first log line to
+which the description belongs to. The absolute number of logs included
+in the description follows. Note that the Zookeeper dataset needs to be
+sorted according to the timestamps in order to make sense. In addition,
+also note that the analysis is coarse-grained but also finer whenever
+new logs that did not appear before take place.
+```
++-----------------------------------------------------------------------+
+| 2015-07-29 17:41:41,536 Logs 1 to 13 |
+| |
+| Startup process from Zookeeper, reading configuration, configuring |
+| quorum, data directory cleanup, quorum peer process starting (which |
+| is responsible for managing the zookeeper ensemble). |
++=======================================================================+
+| 2015-07-29 17:41:41,692 Logs 14 to 44 |
+| |
+| Election leader process. The server binds the port. The server myid=1 |
+| enters the LOOKING state which means it is looking for a leader. The |
+| server proposes itself (0x0). It logs that there are connection |
+| issues to server 10.10.34.12 and 13. Finally receives a connection |
+| request from 10.10.34.12 showing that it is also on the looking |
+| state. |
++-----------------------------------------------------------------------+
+| 2015-07-29 17:42:28,519 Logs 45 to 63 |
+| |
+| Server transitions to the FOLLOWING state, meaning it found a Leader. |
+| The server logs configuration and so on. The election process is |
+| finished and notified its length. |
++-----------------------------------------------------------------------+
+| 2015-07-29 17:42:28,588 Logs 64 to 105 |
+| |
+| Before anything significant, another election process starts. The |
+| server myid=2 starts LOOKING and in the end it starts LEADING, thus |
+| replacing myid=1. |
++-----------------------------------------------------------------------+
+| 2015-07-29 17:42:30:418 Logs 106 to 203 |
+| |
+| Yet another election process starts with server myid=3 proposing |
+| itself, but there are connection problems, response notifications are |
+| taking very long. Server 2 becomes the new leader eventually. |
++-----------------------------------------------------------------------+
+| 2015-07-29 17:46:17,171 Logs 204 to 3,582 |
+| |
+| Connection requests from followers to the leaders occur with errors |
+| all the time (connection request, then connection broken, then |
+| interrupting, then some GOODBYES). These happen intertwined with |
+| "Unexpected exception causing shutdown while socket still open". |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:21:26,842 Logs 3,582 to 53,161 |
+| |
+| Connection requests are still failing but now without the unexpected |
+| exception. Simply being broken. |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:37:24,535 Logs 53,162 to 53,206 |
+| |
+| Finally, connections from clients begin. Before it was all servers. |
+| Connections are established. New log files are created as well. |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:37:27,211 Logs 53,206 to 53,218 |
+| |
+| Multiple errors from clients trying to create nodes which already |
+| exist (files). For example, "/home". |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:48:31,603 Logs 53,219 to 53,312 |
+| |
+| Connection requests from clients along with first-time ever properly |
+| closing sockets (and end of stream exceptions). |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:52:16,000 Logs 53,341 to 53,541 |
+| |
+| First ever messages of expiring sessions from clients because of |
+| timeout. Messages about the processed session termination follow. |
+| They get intertwined with standard client connection requests and |
+| established sessions. |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:53:09,882 Logs 53,542 to 53,800 |
+| |
+| Follower has an exception and shuts down (server myid=3) (note that |
+| the leader is myid=2). It calls for shutdown and closes multiple |
+| connections of clients it had open. After it shuts down, it |
+| transitions to LOOKING to find the leader again. It also reads the |
+| snapshot to restore state. Multiple rounds of notifications take |
+| place for voting the new leader. Server myid=2 is the new leader. It |
+| was already leader, but since myid=3 had some problems, it triggered |
+| a new election. Meanwhile there are many client and server |
+| connections. |
++-----------------------------------------------------------------------+
+| 2015-07-29 19:56:52,122 Logs 53,801 to 58,878 |
+| |
+| Standard sessions and connections are requested, established and |
+| finished (expiring and being closed as well). Some finish with the |
+| end of stream exception, but nothing significant. A node exists error |
+| is also there. |
++-----------------------------------------------------------------------+
+| 2015-07-30 17:40:45,765 Logs 58,879 to 58,945 |
+| |
+| Connection is lost with myid=1 from myid=2 and myid=3. Therefore, a |
+| new election is triggered. The severs are on the LOOKING state. The |
+| "Have smaller server identified" log appears for the first time. The |
+| new leader is myid=1. |
++-----------------------------------------------------------------------+
+| 2015-07-30 17:49:00,254 Logs 58,945 to 59,044 |
+| |
+| Normal processing. Another exception when following leader from |
+| myid=3. New election triggered. Meanwhile everything normal. |
++-----------------------------------------------------------------------+
+| **\*All logs between 59,044 and 70,383\*** |
+| |
+| Now up until the end, multiple elections happen because there is |
+| always one server crashing every once in a while. Always intertwined |
+| with normal processing, but of less duration. Sometimes a new log |
+| file is also created -- this depends on epochs and so on. |
++-----------------------------------------------------------------------+
+| 2015-08-24 15:26:54,671 Logs 70,383 to 73,993 |
+| |
+| After a lot of the previously described, a new election is initiated |
+| by myid=1, but this one is flawed. The server myid=1 is complaining |
+| for long about not being able to open a connection to myid=2 and |
+| myid=3. This lasts for long until finally elections are resolved and |
+| the new leader is myid=2. |
++-----------------------------------------------------------------------+
+| 2015-08-25 08:03:15,876 Logs 73,993 to end (74,380) |
+| |
+| A couple elections more take place in a similar fashion, but no |
+| connection errors between servers. There is no shutdown or anything |
+| of similar nature at the end. |
++-----------------------------------------------------------------------+
+```
+Snippet 1. Manual analysis of the Zookeeper log collection.
+
+## Large Language Model summarization
+
+In this section, a general Large Language Model (LLM) is used to further
+summarize and compare the logging information contained within
+checkpoints in the Time Curve analysis. While fine-tuning a custom Small
+Language Model is intended for future work, we show that a general LLM
+without any prior training or prompts is able to help with the
+summarization. This is the case due to these large models (such as GPT 4
+\[3\]) being trained on large corpus of text which typically
+include logs from the analysed datasets (e.g., Flink or Zookeeper).
+
+The interaction with Microsoft Copilot used for generating the answers
+in Section 4-B is recorded below. Quoted answers in the paper are
+highlighted in dark red.
+
+### Query about single checkpoint summarization in Label C
+```
++-----------------------------------------------------------------------+
+| |
+| Can you summarize for me the following templates which correspond to |
+| logs from an apache zookeeper service? In particular, what is |
+| happening in the system? |
+| |
+| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
+| still open |
+| |
+| \- INFO \<\*\> - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> to \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
+| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
+| snapdir /var/lib/zookeeper/version-2 |
+| |
+| \- INFO \<\*\> - Creating new log file: \<\*\> |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
+| |
+| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
+| |
+| \- INFO \<\*\> - Have smaller server identifier, so dropping the |
+| connection: \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
+| |
+| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
+| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
+| (n.peerEPoch), \<\*\> (my state) |
+| |
+| \- INFO \<\*\> - Reading snapshot \<\*\> |
+| |
+| \- INFO \<\*\> - Received connection request \<\*\> |
+| |
+| \- INFO \<\*\> - Server environment:java.vendor=Oracle Corporation |
+| |
+| \- INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
+| built on 06/10/2013 17:26 GMT |
+| |
+| \- INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
+| \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - TCP NoDelay set to: true |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My election |
+| bind port: 0.0.0.0/0.0.0.0:3888 |
+| |
+| \- INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
+| scheduled. |
+| |
+| \- INFO \[main:QuorumPeerConfig\@101\] - Reading configuration from: |
+| /etc/zookeeper/conf/zoo.cfg |
+| |
+| \- INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
+| |
+| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
+| |
+| \- WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> error |
+| = |
+| |
+| \- WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
+| |
+| \- WARN \<\*\> - Interrupted while waiting for message on queue |
+| |
+| \- WARN \<\*\> - Interrupting SendWorker |
+| |
+| \- WARN \<\*\> - Send worker leaving thread |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o modeCopilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Certainly! Here's a summary of what is happening in the system based |
+| on the provided Apache ZooKeeper log templates: |
+| |
+| **Summary of Log Events** |
+| |
+| 1. **Unexpected Shutdown**: |
+| |
+| - ERROR \<\*\> - Unexpected exception causing shutdown while |
+| sock still open |
+| |
+| - An unexpected exception has caused the server to shut down |
+| while a socket was still open. |
+| |
+| 2. **Leader Election**: |
+| |
+| - INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
+| |
+| - The leader election process has taken place. |
+| |
+| 3. **Client Connections**: |
+| |
+| - INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at |
+| \<\*\> |
+| |
+| - A client is attempting to connect to the ZooKeeper server. |
+| |
+| - INFO \<\*\> - Closed socket connection for client \<\*\> |
+| which had sessionid \<\*\> |
+| |
+| - The server has closed a socket connection for a client, |
+| identified by a session ID. |
+| |
+| - INFO \<\*\> - Established session \<\*\> with negotiated |
+| timeout \<\*\> for client \<\*\> |
+| |
+| - A new session has been successfully established with a |
+| client, including a negotiated timeout. |
+| |
+| - INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFact |
+| ory\@197\] - |
+| Accepted socket connection from \<\*\> |
+| |
+| - The server has accepted a new socket connection from a |
+| client. |
+| |
+| 4. **Session Management**: |
+| |
+| - INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - |
+| Processed session termination for sessionid: \<\*\> |
+| |
+| - The server has processed the termination of a session, |
+| identified by a session ID. |
+| |
+| - INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring |
+| session \<\*\> timeout of \<\*\> exceeded |
+| |
+| - A session has expired because its timeout period was |
+| exceeded. |
+| |
+| 5. **Server Initialization and Configuration**: |
+| |
+| - INFO \<\*\> - Created server with tickTime 2000 |
+| minSessionTimeout 4000 maxSessionTimeout 40000 datadir |
+| /var/lib/zookeeper/version-2 snapdir |
+| /var/lib/zookeeper/version-2 |
+| |
+| - The server has been created with specific configuration |
+| parameters. |
+| |
+| - INFO \[main:QuorumPeerConfig\@101\] - Reading configuration |
+| from: /etc/zookeeper/conf/zoo.cfg |
+| |
+| - The server is reading its configuration from a specified |
+| file. |
+| |
+| - INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
+| |
+| - The quorum peer is starting. |
+| |
+| 6. **Synchronization and Data Management**: |
+| |
+| - INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
+| \<\*\> \<\*\> |
+| |
+| - The server is synchronizing with a follower. |
+| |
+| - INFO \<\*\> - Getting a diff from the leader \<\*\> |
+| |
+| - The server is getting a differential update from the leader. |
+| |
+| - INFO \<\*\> - Reading snapshot \<\*\> |
+| |
+| - The server is reading a snapshot. |
+| |
+| 7. **Warnings and Errors**: |
+| |
+| - WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> |
+| error = |
+| |
+| - A connection has been broken for a specific client ID. |
+| |
+| - WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@34 |
+| 9\] - |
+| caught end of stream exception |
+| |
+| - The server encountered an end-of-stream exception, indicating |
+| an unexpected disconnection. |
+| |
+| - WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@ |
+| 793\] - |
+| Connection request from old client \<\*\> will be dropped if |
+| server is in r-o mode |
+| |
+| - A connection request from an old client will be dropped if |
+| the server is in read-only mode. |
+| |
+| **Overall System Activity** |
+| |
+| The logs indicate that the ZooKeeper server is actively managing |
+| client connections and sessions, handling leader elections, |
+| initializing and configuring the server, and synchronizing data with |
+| followers. The server also deals with various warnings and errors, |
+| such as unexpected shutdowns, broken connections, and session |
+| expirations. |
+| |
+| Is there a specific part of this process you'd like to explore |
+| further? |
+| |
+| You |
+| |
+| **Sent by you:** |
+| |
+| Should I be worried about the errors? |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Errors in your ZooKeeper logs, especially those causing shutdowns, |
+| should definitely be investigated. Here are some steps to help you |
+| understand and address these errors: |
+| |
+| **Key Error to Address** |
+| |
+| - **Unexpected Exception Causing Shutdown**: |
+| |
+| - ERROR \<\*\> - Unexpected exception causing shutdown while |
+| sock still open |
+| |
+| - This indicates a critical issue that caused the server to |
+| shut down unexpectedly. It's important to identify the root |
+| cause to prevent future occurrences. |
+| |
+| **Potential Causes and Actions** |
+| |
+| 1. **Software Bugs**: |
+| |
+| - **Cause**: There might be a bug in the ZooKeeper software or |
+| your application. |
+| |
+| - **Action**: Check for any available updates or patches for |
+| ZooKeeper. Review recent changes in your application that |
+| might have introduced the issue. |
+| |
+| 2. **Resource Exhaustion**: |
+| |
+| - **Cause**: The server might be running out of resources |
+| (e.g., memory, CPU). |
+| |
+| - **Action**: Monitor resource usage on the server. Consider |
+| increasing resources or optimizing the application to use |
+| fewer resources. |
+| |
+| 3. **Network Issues**: |
+| |
+| - **Cause**: Network instability can cause unexpected |
+| disconnections and errors. |
+| |
+| - **Action**: Ensure that the network is stable and reliable. |
+| Check for any network configuration issues or hardware |
+| problems. |
+| |
+| 4. **Configuration Problems**: |
+| |
+| - **Cause**: Incorrect or suboptimal configuration settings can |
+| lead to errors. |
+| |
+| - **Action**: Review your ZooKeeper configuration settings. |
+| Ensure they are set according to best practices and your |
+| specific use case. |
+| |
+| **Monitoring and Prevention** |
+| |
+| - **Log Monitoring**: Continuously monitor your logs for errors and |
+| warnings. Set up alerts for critical issues. |
+| |
+| - **Regular Maintenance**: Perform regular maintenance tasks, such |
+| as cleaning up old data and ensuring the server is running |
+| optimally. |
+| |
+| - **Testing**: Test your application and ZooKeeper setup in a |
+| staging environment before deploying changes to production. |
+| |
+| **Conclusion** |
+| |
+| While occasional errors might not be a cause for immediate concern, |
+| frequent or critical errors like unexpected shutdowns should be |
+| addressed promptly to ensure the stability and reliability of your |
+| ZooKeeper service. |
+| |
+| Would you like more detailed guidance on any of these steps or have |
+| any specific concerns about your setup? |
++-----------------------------------------------------------------------+
+```
+Snippet 2. Single checkpoint summarization in Label `C`.
+
+### Query about single checkpoint summarization in Label D
+```
++-----------------------------------------------------------------------+
+| |
+| Can you summarize for me the following templates which correspond to |
+| logs from an apache zookeeper service? In particular, what is |
+| happening in the system? |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Certainly! Here's a summary of what is happening in the system based |
+| on the provided Apache ZooKeeper log templates: |
+| |
+| **Summary of Log Events** |
+| |
+| 1. **Client Connection Attempts**: |
+| |
+| - INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at |
+| \<\*\> |
+| |
+| - A client is trying to connect to the ZooKeeper server. |
+| |
+| 2. **Socket Connection Closure**: |
+| |
+| - INFO \<\*\> - Closed socket connection for client \<\*\> |
+| which had sessionid \<\*\> |
+| |
+| - The server has closed a socket connection for a client, |
+| identified by a session ID. |
+| |
+| 3. **Session Establishment**: |
+| |
+| - INFO \<\*\> - Established session \<\*\> with negotiated |
+| timeout \<\*\> for client \<\*\> |
+| |
+| - A new session has been successfully established with a |
+| client, including a negotiated timeout. |
+| |
+| 4. **Session Termination Processing**: |
+| |
+| - INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - |
+| Processed session termination for sessionid: \<\*\> |
+| |
+| - The server has processed the termination of a session, |
+| identified by a session ID. |
+| |
+| 5. **Socket Connection Acceptance**: |
+| |
+| - INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFact |
+| ory\@197\] - |
+| Accepted socket connection from \<\*\> |
+| |
+| - The server has accepted a new socket connection from a |
+| client. |
+| |
+| 6. **Session Expiration**: |
+| |
+| - INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring |
+| session \<\*\> timeout of \<\*\> exceeded |
+| |
+| - A session has expired because its timeout period was |
+| exceeded. |
+| |
+| 7. **End of Stream Exception**: |
+| |
+| - WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@34 |
+| 9\] - |
+| caught end of stream exception |
+| |
+| - The server encountered an end-of-stream exception, indicating |
+| an unexpected disconnection. |
+| |
+| 8. **Connection Request from Old Client**: |
+| |
+| - WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@ |
+| 793\] - |
+| Connection request from old client \<\*\> will be dropped if |
+| server is in r-o mode |
+| |
+| - A connection request from an old client will be dropped if |
+| the server is in read-only mode. |
+| |
+| **Overall System Activity** |
+| |
+| The logs indicate that the ZooKeeper server is actively managing |
+| client connections and sessions. It handles new connection attempts, |
+| establishes and terminates sessions, and processes session |
+| expirations. The server also deals with connection issues, such as |
+| end-of-stream exceptions and connection requests from outdated |
+| clients. |
+| |
+| Is there a specific part of this process you'd like to dive deeper |
+| into? |
+| |
+| You |
+| |
+| **Sent by you:** |
+| |
+| Should I be worried about the end-of-stream exceptions? |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| End-of-stream exceptions in ZooKeeper logs can indicate that a client |
+| connection was unexpectedly closed. While these exceptions are not |
+| uncommon and can occur for various reasons, they are worth |
+| monitoring. Here are a few considerations: |
+| |
+| **Potential Causes** |
+| |
+| 1. **Network Issues**: Temporary network disruptions can cause |
+| clients to disconnect unexpectedly. |
+| |
+| 2. **Client-Side Problems**: The client application might be |
+| experiencing issues or crashes. |
+| |
+| 3. **Server Overload**: The server might be under heavy load, |
+| causing it to drop connections. |
+| |
+| **Impact** |
+| |
+| - **Transient Issues**: If these exceptions are infrequent, they |
+| might not significantly impact the system. |
+| |
+| - **Persistent Problems**: Frequent end-of-stream exceptions could |
+| indicate underlying issues that need to be addressed, such as |
+| network instability or server performance problems. |
+| |
+| **Actions to Take** |
+| |
+| 1. **Monitor Frequency**: Keep an eye on how often these exceptions |
+| occur. A sudden increase might warrant further investigation. |
+| |
+| 2. **Check Network Stability**: Ensure that the network between |
+| clients and the server is stable and reliable. |
+| |
+| 3. **Review Client Logs**: Look at the client-side logs to see if |
+| there are any corresponding errors or issues. |
+| |
+| 4. **Server Performance**: Monitor the server's performance metrics |
+| to ensure it is not overloaded. |
+| |
+| If the end-of-stream exceptions are causing noticeable issues or if |
+| their frequency increases, it would be a good idea to investigate |
+| further to identify and resolve the root cause. |
+| |
+| Would you like more detailed steps on how to monitor and troubleshoot |
+| these exceptions? |
++-----------------------------------------------------------------------+
+```
+Snippet 3. Single checkpoint summarization in Label `D`.
+
+### Query about pairwise comparison between checkpoints in Label D
+```
++-----------------------------------------------------------------------+
+| |
+| Can you tell me the difference between these two set of logs? |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode |
+| |
+| And this other one: |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[ProcessThread(sid:2 cport:-1)::PrepRequestProcessor\@627\] |
+| - Got user-level KeeperException when processing \<\*\> type:create |
+| \<\*\> \<\*\> txntype:-1 reqpath:n/a Error \<\*\> |
+| Error:KeeperErrorCode = NodeExists for \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Certainly! Here are the differences between the two sets of logs: |
+| |
+| 1. **Additional INFO Log**: |
+| |
+| - **Second Set**: Contains an additional INFO log: |
+| |
+| - INFO \[ProcessThread(sid:2 |
+| cport:-1)::PrepRequestProcessor\@627\] - Got user-level |
+| KeeperException when processing \<\*\> type:create \<\*\> |
+| \<\*\> txntype:-1 reqpath:n/a Error \<\*\> |
+| Error:KeeperErrorCode = NodeExists for \<\*\> |
+| |
+| This log indicates a KeeperException due to a node already existing. |
+| |
+| 2. **Error Log Presence**: |
+| |
+| - **First Set**: Does not contain the KeeperException log |
+| mentioned above. |
+| |
+| These differences suggest that the second set of logs includes an |
+| additional event where a KeeperException occurred, indicating an |
+| attempt to create a node that already exists. |
+| |
+| Is there anything specific you need help with regarding these logs? |
+| |
+| You |
+| |
+| **Sent by you:** |
+| |
+| Is this \"KeeperException\" a serious error? |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| A KeeperException in ZooKeeper can vary in severity depending on the |
+| specific type of exception. The NodeExistsException, which is |
+| mentioned in your logs, indicates that an attempt was made to create |
+| a node that already exists. [This is generally not a critical error |
+| but rather an indication that the operation needs to handle the |
+| existence of the node more |
+| gracefully^1^](https://zookeeper.apache.org/doc/r3.3.3/api/org/apache |
+| /zookeeper/KeeperException.html). |
+| |
+| [However, other types of KeeperException can be more serious, such |
+| as ConnectionLossException or SessionExpiredException, which indicate |
+| issues with the connection to the ZooKeeper server or session |
+| management^1^](https://zookeeper.apache.org/doc/r3.3.3/api/org/apache |
+| /zookeeper/KeeperException.html). |
+| |
+| Would you like more details on handling specific types |
+| of KeeperException? |
++-----------------------------------------------------------------------+
+```
+Snippet 4. Pairwise checkpoint summarization in Label `D`.
+
+### Query about pairwise comparison between Label C and E
+
+```
++-----------------------------------------------------------------------+
+| |
+| Can you please tell me the similarities between these two sets of log |
+| lines from the Apache Zookeeper system? |
+| |
+| \- ERROR \<\*\> - Unexpected Exception: |
+| |
+| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
+| still open |
+| |
+| \- INFO \<\*\> - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> to \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
+| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
+| snapdir /var/lib/zookeeper/version-2 |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
+| |
+| \- INFO \<\*\> - Have smaller server identifier, so dropping the |
+| connection: \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
+| |
+| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
+| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
+| (n.peerEPoch), \<\*\> (my state) |
+| |
+| \- INFO \<\*\> - Reading snapshot \<\*\> |
+| |
+| \- INFO \<\*\> - Received connection request \<\*\> |
+| |
+| \- INFO \<\*\> - Server environment:java.vendor=Oracle Corporation |
+| |
+| \- INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
+| built on 06/10/2013 17:26 GMT |
+| |
+| \- INFO \<\*\> - TCP NoDelay set to: true |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My election |
+| bind port: 0.0.0.0/0.0.0.0:3888 |
+| |
+| \- INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
+| scheduled. |
+| |
+| \- INFO \[main:QuorumPeerConfig\@101\] - Reading configuration from: |
+| /etc/zookeeper/conf/zoo.cfg |
+| |
+| \- INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
+| |
+| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
+| |
+| \- WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> error |
+| = |
+| |
+| \- WARN \<\*\> - Interrupted while waiting for message on queue |
+| |
+| \- WARN \<\*\> - Interrupting SendWorker |
+| |
+| \- WARN \<\*\> - Send worker leaving thread |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode And this other one: |
+| |
+| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
+| still open |
+| |
+| \- INFO \<\*\> - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> exited loop! |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
+| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
+| snapdir /var/lib/zookeeper/version-2 |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
+| |
+| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
+| |
+| \- INFO \<\*\> - Have quorum of supporters starting up and setting |
+| last processed zxid: \<\*\> |
+| |
+| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
+| |
+| \- INFO \<\*\> - Notification time out: \<\*\> |
+| |
+| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
+| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
+| (n.peerEPoch), \<\*\> (my state) |
+| |
+| \- INFO \<\*\> - Reading snapshot \<\*\> |
+| |
+| \- INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
+| \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - shutdown of request processor complete |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@143\] - |
+| PrepRequestProcessor exited loop! |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner\@107\] - |
+| Revalidating client: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@1001\] - |
+| Closed socket connection for client \<\*\> (no session established |
+| for client) |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- INFO \[Thread-2:Leader\$LearnerCnxAcceptor\@309\] - exception |
+| while shutting down acceptor: java.net.SocketException: Socket closed |
+| |
+| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
+| |
+| \- WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
+| |
+| \- WARN \<\*\> - Exception when following the leader |
+| |
+| \- WARN \<\*\> - First is 0x0 |
+| |
+| \- WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@354\] - |
+| Exception causing close of session 0x0 due to java.io.IOException: |
+| ZooKeeperServer not running |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Certainly! Here are the similarities between the two sets of log |
+| lines from the Apache Zookeeper system: |
+| |
+| 1. **Log Levels**: Both sets include log lines with ERROR, INFO, |
+| and WARN levels, indicating different severities of events. |
+| |
+| 2. **Placeholders**: Both sets use placeholders (\<\*\>) to |
+| anonymize specific details such as session IDs, client IDs, or |
+| other dynamic values. |
+| |
+| 3. **Common Events**: |
+| |
+| - **Unexpected Exceptions**: Both sets have ERROR logs related |
+| to unexpected exceptions causing shutdowns. |
+| |
+| - **Leader Election**: Both sets include INFO logs about the |
+| leader election process. |
+| |
+| - **Socket Connections**: Both sets log information about |
+| socket connections being opened or closed. |
+| |
+| - **Session Management**: Both sets include logs about session |
+| creation, termination, and expiration. |
+| |
+| - **Snapshot Reading**: Both sets have logs related to reading |
+| snapshots. |
+| |
+| - **Client Requests**: Both sets log client connection requests |
+| and attempts. |
+| |
+| 4. **Server Environment**: Both sets include logs about the server |
+| environment and configuration details, such as Java vendor and |
+| Zookeeper version. |
+| |
+| 5. **Warnings**: Both sets contain WARN logs about connection |
+| issues, interruptions, and exceptions during operations. |
+| |
+| 6. **Specific Processes**: |
+| |
+| - **Leader Election Details**: Both sets provide detailed logs |
+| about the leader election process, including notifications |
+| and proposals. |
+| |
+| - **Session Handling**: Both sets log the establishment and |
+| termination of sessions, including details about session IDs |
+| and timeouts. |
+| |
+| - **Client Interactions**: Both sets include logs about client |
+| interactions, such as connection attempts and socket |
+| closures. |
+| |
+| These similarities indicate that both sets of logs are from the |
+| Apache Zookeeper system, capturing various operational events and |
+| issues related to leader election, session management, and client |
+| connections. |
+| |
+| You |
+| |
+| **Sent by you:** |
+| |
+| Could you please tell me what is the difference between these two |
+| sets of logs? |
+| |
+| \- ERROR \<\*\> - Unexpected Exception: |
+| |
+| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
+| still open |
+| |
+| \- INFO \<\*\> - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> to \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
+| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
+| snapdir /var/lib/zookeeper/version-2 |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
+| |
+| \- INFO \<\*\> - Have smaller server identifier, so dropping the |
+| connection: \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
+| |
+| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
+| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
+| (n.peerEPoch), \<\*\> (my state) |
+| |
+| \- INFO \<\*\> - Reading snapshot \<\*\> |
+| |
+| \- INFO \<\*\> - Received connection request \<\*\> |
+| |
+| \- INFO \<\*\> - Server environment:java.vendor=Oracle Corporation |
+| |
+| \- INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
+| built on 06/10/2013 17:26 GMT |
+| |
+| \- INFO \<\*\> - TCP NoDelay set to: true |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My election |
+| bind port: 0.0.0.0/0.0.0.0:3888 |
+| |
+| \- INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
+| scheduled. |
+| |
+| \- INFO \[main:QuorumPeerConfig\@101\] - Reading configuration from: |
+| /etc/zookeeper/conf/zoo.cfg |
+| |
+| \- INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
+| |
+| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
+| |
+| \- WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> error |
+| = |
+| |
+| \- WARN \<\*\> - Interrupted while waiting for message on queue |
+| |
+| \- WARN \<\*\> - Interrupting SendWorker |
+| |
+| \- WARN \<\*\> - Send worker leaving thread |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode And this other one: |
+| |
+| \- ERROR \<\*\> - Unexpected exception causing shutdown while sock |
+| still open |
+| |
+| \- INFO \<\*\> - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> - LEADER ELECTION TOOK - \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> \<\*\> to \<\*\> |
+| |
+| \- INFO \<\*\> - \<\*\> exited loop! |
+| |
+| \- INFO \<\*\> - Client attempting to \<\*\> \<\*\> \<\*\> at \<\*\> |
+| |
+| \- INFO \<\*\> - Closed socket connection for client \<\*\> which had |
+| sessionid \<\*\> |
+| |
+| \- INFO \<\*\> - Created server with tickTime 2000 minSessionTimeout |
+| 4000 maxSessionTimeout 40000 datadir /var/lib/zookeeper/version-2 |
+| snapdir /var/lib/zookeeper/version-2 |
+| |
+| \- INFO \<\*\> - Established session \<\*\> with negotiated timeout |
+| \<\*\> for client \<\*\> |
+| |
+| \- INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
+| |
+| \- INFO \<\*\> - Getting a diff from the leader \<\*\> |
+| |
+| \- INFO \<\*\> - Have quorum of supporters starting up and setting |
+| last processed zxid: \<\*\> |
+| |
+| \- INFO \<\*\> - New election. My id = \<\*\> proposed \<\*\> |
+| |
+| \- INFO \<\*\> - Notification time out: \<\*\> |
+| |
+| \- INFO \<\*\> - Notification: \<\*\> (n.leader), \<\*\> (n.zxid), |
+| \<\*\> (n.round), \<\*\> (n.state), \<\*\> (n.sid), \<\*\> |
+| (n.peerEPoch), \<\*\> (my state) |
+| |
+| \- INFO \<\*\> - Reading snapshot \<\*\> |
+| |
+| \- INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
+| \<\*\> \<\*\> |
+| |
+| \- INFO \<\*\> - shutdown of request processor complete |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@143\] - |
+| PrepRequestProcessor exited loop! |
+| |
+| \- INFO \<\*\> cport:-1)::PrepRequestProcessor\@476\] - Processed |
+| session termination for sessionid: \<\*\> |
+| |
+| \- INFO \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner\@107\] - |
+| Revalidating client: \<\*\> |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@1001\] - |
+| Closed socket connection for client \<\*\> (no session established |
+| for client) |
+| |
+| \- INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory\@197 |
+| \] |
+| - Accepted socket connection from \<\*\> |
+| |
+| \- INFO \[SessionTracker:ZooKeeperServer\@325\] - Expiring session |
+| \<\*\> timeout of \<\*\> exceeded |
+| |
+| \- INFO \[Thread-2:Leader\$LearnerCnxAcceptor\@309\] - exception |
+| while shutting down acceptor: java.net.SocketException: Socket closed |
+| |
+| \- WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
+| |
+| \- WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
+| |
+| \- WARN \<\*\> - Exception when following the leader |
+| |
+| \- WARN \<\*\> - First is 0x0 |
+| |
+| \- WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] - |
+| caught end of stream exception |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@354\] - |
+| Exception causing close of session 0x0 due to java.io.IOException: |
+| ZooKeeperServer not running |
+| |
+| \- WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Sure! Here are the differences between the two sets of logs: |
+| |
+| 1. **Error Logs**: |
+| |
+| - **First Set**: Contains two error logs: |
+| |
+| - ERROR \<\*\> - Unexpected Exception: |
+| |
+| - ERROR \<\*\> - Unexpected exception causing shutdown while |
+| sock still open |
+| |
+| - **Second Set**: Contains only one error log: |
+| |
+| - ERROR \<\*\> - Unexpected exception causing shutdown while |
+| sock still open |
+| |
+| 2. **INFO Logs**: |
+| |
+| - **First Set**: Includes the following INFO logs not present |
+| in the second set: |
+| |
+| - INFO \<\*\> - Have smaller server identifier, so dropping the |
+| connection: \<\*\> \<\*\> |
+| |
+| - INFO \<\*\> - Received connection request \<\*\> |
+| |
+| - INFO \<\*\> - Server environment:java.vendor=Oracle |
+| Corporation |
+| |
+| - INFO \<\*\> - Server environment:zookeeper.version=3.4.5\--1, |
+| built on 06/10/2013 17:26 GMT |
+| |
+| - INFO \<\*\> - TCP NoDelay set to: true |
+| |
+| - INFO \[Thread-1:QuorumCnxManager\$Listener\@486\] - My |
+| election bind port: 0.0.0.0/0.0.0.0:3888 |
+| |
+| - INFO \[main:DatadirCleanupManager\@101\] - Purge task is not |
+| scheduled. |
+| |
+| - INFO \[main:QuorumPeerConfig\@101\] - Reading configuration |
+| from: /etc/zookeeper/conf/zoo.cfg |
+| |
+| - INFO \[main:QuorumPeerMain\@127\] - Starting quorum peer |
+| |
+| - **Second Set**: Includes the following INFO logs not present |
+| in the first set: |
+| |
+| - INFO \<\*\> - \<\*\> exited loop! |
+| |
+| - INFO \<\*\> - Follower sid: \<\*\> : info : \<\*\> |
+| |
+| - INFO \<\*\> - Have quorum of supporters starting up and |
+| setting last processed zxid: \<\*\> |
+| |
+| - INFO \<\*\> - Notification time out: \<\*\> |
+| |
+| - INFO \<\*\> - Synchronizing with Follower sid: \<\*\> \<\*\> |
+| \<\*\> \<\*\> |
+| |
+| - INFO \<\*\> - shutdown of request processor complete |
+| |
+| - INFO \<\*\> cport:-1)::PrepRequestProcessor\@143\] - |
+| PrepRequestProcessor exited loop! |
+| |
+| - INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner\@107\] - |
+| Revalidating client: \<\*\> |
+| |
+| - INFO |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@10 |
+| 01\] - |
+| Closed socket connection for client \<\*\> (no session |
+| established for client) |
+| |
+| - INFO \[Thread-2:Leader\$LearnerCnxAcceptor\@309\] - exception |
+| while shutting down acceptor: java.net.SocketException: |
+| Socket closed |
+| |
+| 3. **WARN Logs**: |
+| |
+| - **First Set**: Contains the following WARN logs not present |
+| in the second set: |
+| |
+| - WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> |
+| error = |
+| |
+| - WARN \<\*\> - Interrupted while waiting for message on queue |
+| |
+| - WARN \<\*\> - Interrupting SendWorker |
+| |
+| - WARN \<\*\> - Send worker leaving thread |
+| |
+| - **Second Set**: Contains the following WARN logs not present |
+| in the first set: |
+| |
+| - WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
+| |
+| - WARN \<\*\> - Exception when following the leader |
+| |
+| - WARN \<\*\> - First is 0x0 |
+| |
+| - WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
+| |
+| - WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@35 |
+| 4\] - |
+| Exception causing close of session 0x0 due to |
+| java.io.IOException: ZooKeeperServer not running |
+| |
+| These differences indicate that the first set of logs includes more |
+| detailed information about the server environment and configuration, |
+| while the second set includes more details about the election process |
+| and issues encountered during synchronization and session management. |
+| |
+| Is there anything specific you need help with regarding these logs? |
+| |
+| You |
+| |
+| **Sent by you:** |
+| |
+| Can you be more specific about the differences of WARN logs? What is |
+| changing betweem the two? |
+| |
+| Copilot |
+| |
+| **Sent by Copilot:** |
+| |
+| Certainly! Here are the specific differences in the WARN logs between |
+| the two sets: |
+| |
+| 1. **First Set**: |
+| |
+| - **Connection Issues**: |
+| |
+| - WARN \<\*\> - Connection broken for id \<\*\> my id = \<\*\> |
+| error = |
+| |
+| - WARN \<\*\> - Interrupted while waiting for message on queue |
+| |
+| - WARN \<\*\> - Interrupting SendWorker |
+| |
+| - WARN \<\*\> - Send worker leaving thread |
+| |
+| These logs indicate issues with connection stability and |
+| interruptions in the message queue and send worker processes. |
+| |
+| 2. **Second Set**: |
+| |
+| - **Leader and Session Issues**: |
+| |
+| - WARN \<\*\> - Commiting zxid \<\*\> from \<\*\> not first! |
+| |
+| - WARN \<\*\> - Exception when following the leader |
+| |
+| - WARN \<\*\> - First is 0x0 |
+| |
+| - WARN \<\*\> - Got zxid \<\*\> expected \<\*\> |
+| |
+| - WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@35 |
+| 4\] - |
+| Exception causing close of session 0x0 due to |
+| java.io.IOException: ZooKeeperServer not running |
+| |
+| These logs highlight issues related to leader election and |
+| synchronization, such as unexpected zxid values and exceptions when |
+| following the leader, as well as a specific session closure due to |
+| the server not running. |
+| |
+| Both sets share some common WARN logs related to connection issues: |
+| |
+| WARN \<\*\> - \*\*\*\*\*\*\* GOODBYE \<\*\> \*\*\*\*\*\*\*\* |
+| |
+| WARN \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn\@349\] |
+| - caught end of stream exception |
+| |
+| WARN |
+| \[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer\@793\] - |
+| Connection request from old client \<\*\> will be dropped if server |
+| is in r-o mode |
+| |
+| These differences suggest that the first set focuses more on |
+| connection stability and worker interruptions, while the second set |
+| emphasizes leader election and synchronization issues. |
+| |
+| Is there anything else you need help with regarding these logs? |
++-----------------------------------------------------------------------+
+```
+Snippet 5. Pairwise checkpoint summarization between Labels `C` and `D`.
+
+## Log datasets
+
+The following datasets were employed for each of the evaluation sections. These range in sizes from just a few thousand to four million logs.
+
+- Stream Processing analysis: The [Spark driver](data/spark-driver.log), [Flink job manager](data/flink-job-manager.log) and the [Kafka Streams worker #0](data/kafka-streams-worker-0.log) logs were used.
+- Public dataset analysis: The [Zookeeper](data/Zookeeper.log) log collection from LogPai [4] was used.
+- Multiple curve analysis: A proprietary dataset corresponding to three instances of the same application was used. This included stages such as application initialization, logger configuration, launching a Java server application, awaiting and servicing connections and also shutdown of the instance.
+- Scalability analysis: The HDFS, BGL, Spark and Windows log datasets were used from the [LogHub collection](https://zenodo.org/records/8196385). They were cropped to one million log lines in order to test the runtime as function of the variability.
+
+## Citing
+
+If you use our work, please cite the following paper:
+
+Borysenkov, Dmytro, Adriano Vogel, Sören Henning, and Esteban Perez-Wohlfeil. "Analyzing Logs of Large-Scale Software Systems Using Time Curves Visualization". arXiv [Cs.SE], 2024. arXiv. http://arxiv.org/abs/2411.05533.
+
+## References
+
+1. Koffka, Kurt. *Principles of Gestalt psychology*.
+routledge, 2013.
+
+2. Bach, Benjamin, Conglei Shi, Nicolas Heulot, Tara
+Madhyastha, Tom Grabowski, and Pierre Dragicevic. \"Time curves: Folding
+time to visualize patterns of temporal evolution in data.\" *IEEE
+transactions on visualization and computer graphics* 22, no. 1 (2015):
+559-568.
+
+3. Achiam, Josh, Steven Adler, Sandhini Agarwal, Lama Ahmad,
+Ilge Akkaya, Florencia Leoni Aleman, Diogo Almeida et al. \"Gpt-4
+technical report.\" *arXiv preprint arXiv:2303.08774* (2023).
+
+4. Zhu, Jieming, Shilin He, Pinjia He, Jinyang Liu, and Michael R. Lyu.
+"Loghub: A large collection of system log datasets for ai-driven log
+analytics." In 2023 IEEE 34th International Symposium on Software
+Reliability Engineering (ISSRE), pp. 355-366. IEEE, 2023.
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