Test Samsung PM991a 256GB SSD

[thmang82]

I have just build up a CM4 based mini-server with a Samsung PM991a 2242 M2 265 GB SSD.
SAMSUNG MZALQ256HBJD-00BL2

Important: The quite similar named Samsung PM9B1 does not work (Kernel Error when booted from SD-Card, and mass-storage-gadget does not detect it). Maybe it's because it is PCIe 4.0, instead PCIe 3.0 for the PM991a.

System is based on a WaveShare CM4-IO-BASE-B board.

Speed seems to be quite good, see below.

I got the drive for about 16€ from ebay. They are not available "new" any more, likely stems from some unsold laptops. Was only used for less than 4 hours according to smartctl.

IOZone Speed Test with 4k/1024k Block size and 100MB file size:

        Auto Mode
        File size set to 102400 kB
        Record Size 4 kB
        Record Size 1024 kB
        Command line used: iozone -e -I -a -s 100M -r 4k -r 1024k -i 0 -i 1 -i 2
        Output is in kBytes/sec
        Time Resolution = 0.000001 seconds.
        Processor cache size set to 1024 kBytes.
        Processor cache line size set to 32 bytes.
        File stride size set to 17 * record size.
                                                              random    random                                   
              kB  reclen    write  rewrite    read    reread    read     write
          102400       4    59604    90257    93754    93602    43911    86402                                                                
          102400    1024   373310   379643   388511   388816   370082   366939

SmartCTL result:

sudo smartctl -a /dev/nvme0n1p2
smartctl 7.3 2022-02-28 r5338 [aarch64-linux-6.1.0-rpi7-rpi-v8] (local build)
Copyright (C) 2002-22, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Number:                       SAMSUNG MZALQ256HBJD-00BL2
Serial Number:                      S65FNX0Txxxxxx
Firmware Version:                   5L2QFXM7
PCI Vendor/Subsystem ID:            0x144d
IEEE OUI Identifier:                0x002538
Total NVM Capacity:                 256,060,514,304 [256 GB]
Unallocated NVM Capacity:           0
Controller ID:                      5
NVMe Version:                       1.4
Number of Namespaces:               1
Namespace 1 Size/Capacity:          256,060,514,304 [256 GB]
Namespace 1 Utilization:            6,782,369,792 [6.78 GB]
Namespace 1 Formatted LBA Size:     512
Namespace 1 IEEE EUI-64:            002538 d821b10cc0
Local Time is:                      Tue Dec 12 19:12:18 2023 GMT
Firmware Updates (0x16):            3 Slots, no Reset required
Optional Admin Commands (0x0017):   Security Format Frmw_DL Self_Test
Optional NVM Commands (0x0057):     Comp Wr_Unc DS_Mngmt Sav/Sel_Feat Timestmp
Log Page Attributes (0x0f):         S/H_per_NS Cmd_Eff_Lg Ext_Get_Lg Telmtry_Lg
Maximum Data Transfer Size:         512 Pages
Warning  Comp. Temp. Threshold:     81 Celsius
Critical Comp. Temp. Threshold:     87 Celsius
Namespace 1 Features (0x10):        NP_Fields

Supported Power States
St Op     Max   Active     Idle   RL RT WL WT  Ent_Lat  Ex_Lat
 0 +     5.35W       -        -    0  0  0  0        0       0
 1 +     5.35W       -        -    1  1  1  1        0       0
 2 +     5.35W       -        -    2  2  2  2        0     500
 3 -   0.0500W       -        -    3  3  3  3      210    1200
 4 -   0.0050W       -        -    4  4  4  4     1000    9000

Supported LBA Sizes (NSID 0x1)
Id Fmt  Data  Metadt  Rel_Perf
 0 +     512       0         0

[thomas-lentz]

Hi,
this is really interesting! My search for a problem with my Raspberry CM4 with Samsung PM991 (MZALQ256HAJD) braught me here. I'm using the (almost) exact setup, but I can't get them to run. The moment I'm inserting the SSD into the WaveShare CM4-IO-BASE-B, the boards stops booting until it runs into some sort of timeout and then continues to boot. Using Windows with an USB to M2 Adapter the P991 are running fine (I bought 5 of them). The problem is related to these entries and I can't figure out, what the problem is.

[    1.288572] nvme nvme0: pci function 0000:01:00.0
[    1.288621] nvme 0000:01:00.0: enabling device (0000 -> 0002)
[   62.431806] nvme nvme0: I/O 16 QID 0 timeout, completion polled
[  123.871767] nvme nvme0: I/O 17 QID 0 timeout, completion polled
[  123.871804] nvme nvme0: Shutdown timeout set to 8 seconds
[  185.311746] nvme nvme0: I/O 18 QID 0 timeout, completion polled

I attached the dmesg messages in case you have an idea what the problem might be
dmesg2.txt

I appreciate your help.

Kind regards
Tom

[ned14]

Note that the official Raspberry Pi NVMe SSD is underneath a Samsung PM991a (the 'a' is important). Source: https://www.techpowerup.com/ssd-specs/raspberry-pi-ssd-512-gb.d2227

[geerlingguy]

@ned14 - Indeed! That's what we found while testing the Pi SSD here: #679

[ned14]

Looks like at the time of me writing this right now, used eBay/Aliexpress PM991a SSDs are very similarly priced to the official Raspberry Pi SSD new if you exclude delivery. The difference appears to be basically the delivery charge for new vs used and potentially dodgy vs guaranteed working.

BTW Jeff love your blog have done for ages. Been occasionally following you since you were more a religious blog (I am also a Catholic). Then you seemed to suddenly go into tech, and I was "oh I do that too!". Keep doing what you're doing!