Issue 6374 - nsslapd-mdb-max-dbs autotuning doesn't work properly

dirsrvtests/tests/suites/config/config_test.py

@@ -17,6 +17,7 @@
 from lib389.utils import *
 from lib389._constants import DN_CONFIG, DEFAULT_SUFFIX, DEFAULT_BENAME
 from lib389._mapped_object import DSLdapObjects
+from lib389.agreement import Agreements
 from lib389.cli_base import FakeArgs
 from lib389.cli_conf.backend import db_config_set
 from lib389.idm.user import UserAccounts, TEST_USER_PROPERTIES
@@ -27,6 +28,8 @@
 from lib389.backend import Backends, DatabaseConfig
 from lib389.monitor import MonitorLDBM, Monitor
 from lib389.plugins import ReferentialIntegrityPlugin
+from lib389.replica import BootstrapReplicationManager, Replicas
+from lib389.passwd import password_generate
 
 pytestmark = pytest.mark.tier0
 
@@ -36,6 +39,8 @@
 logging.getLogger(__name__).setLevel(logging.INFO)
 log = logging.getLogger(__name__)
 
+DEBUGGING = os.getenv("DEBUGGING", default=False)
+
 @pytest.fixture(scope="module")
 def big_file():
     TEMP_BIG_FILE = ''
@@ -813,6 +818,87 @@ def test_numlisteners_limit(topo):
     assert numlisteners[0] == '4'
 
 
+def bootstrap_replication(inst_from, inst_to, creds):
+    manager = BootstrapReplicationManager(inst_to)
+    rdn_val = 'replication manager'
+    if  manager.exists():
+        manager.delete()
+    manager.create(properties={
+        'cn': rdn_val,
+        'uid': rdn_val,
+        'userPassword': creds
+    })
+    for replica in Replicas(inst_to).list():
+        replica.remove_all('nsDS5ReplicaBindDNGroup')
+        replica.replace('nsDS5ReplicaBindDN', manager.dn)
+    for agmt in Agreements(inst_from).list():
+        agmt.replace('nsDS5ReplicaBindDN', manager.dn)
+        agmt.replace('nsDS5ReplicaCredentials', creds)
+
+
+@pytest.mark.skipif(get_default_db_lib() != "mdb", reason="This test requires lmdb")
+def test_lmdb_autotuned_maxdbs(topology_m2, request):
+    """Verify that after restart, nsslapd-mdb-max-dbs is large enough to add a new backend.
+
+    :id: 0272d432-9080-11ef-8f40-482ae39447e5
+    :setup: Two suppliers configuration
+    :steps:
+        1. loop 20 times
+        3. In 1 loop: restart instance
+        3. In 1 loop: add a new backend
+        4. In 1 loop: check that instance is still alive
+    :expectedresults:
+        1. Success
+        2. Success
+        3. Success
+        4. Success
+    """
+
+    s1 = topology_m2.ms["supplier1"]
+    s2 = topology_m2.ms["supplier2"]
+
+    backends = Backends(s1)
+    db_config = DatabaseConfig(s1)
+    # Generate the teardown finalizer
+    belist = []
+    creds=password_generate()
+    bootstrap_replication(s2, s1, creds)
+    bootstrap_replication(s1, s2, creds)
+
+    def fin():
+        s1.start()
+        for be in belist:
+            be.delete()
+
+    if not DEBUGGING:
+        request.addfinalizer(fin)
+
+    # 1. Set autotuning (off-line to be able to decrease the value)
+    s1.stop()
+    dse_ldif = DSEldif(s1)
+    dse_ldif.replace(db_config.dn, 'nsslapd-mdb-max-dbs', '0')
+    os.remove(f'{s1.dbdir}/data.mdb')
+    s1.start()
+
+    # 2. Reinitialize the db:
+    log.info("Bulk import...")
+    agmt = Agreements(s2).list()[0]
+    agmt.begin_reinit()
+    (done, error) = agmt.wait_reinit()
+    log.info(f'Bulk importresult is ({done}, {error})')
+    assert done is True
+    assert error is False
+
+    # 3. loop 20 times
+    for idx in range(20):
+        s1.restart()
+        log.info(f'Adding backend test{idx}')
+        belist.append(backends.create(properties={'cn': f'test{idx}',
+                                     'nsslapd-suffix': f'dc=test{idx}'}))
+        assert s1.status()
+
+
+
 if __name__ == '__main__':
     # Run isolated
     # -s for DEBUG mode

ldap/servers/slapd/back-ldbm/back-ldbm.h

@@ -896,4 +896,6 @@ typedef struct _back_search_result_set
     ((L)->size == (R)->size && !memcmp((L)->data, (R)->data, (L)->size))
 
 typedef int backend_implement_init_fn(struct ldbminfo *li, config_info *config_array);
+
+pthread_mutex_t *get_import_ctx_mutex();
 #endif /* _back_ldbm_h_ */

ldap/servers/slapd/back-ldbm/db-mdb/mdb_config.c

@@ -83,7 +83,7 @@ dbmdb_compute_limits(struct ldbminfo *li)
     uint64_t total_space = 0;
     uint64_t avail_space = 0;
     uint64_t cur_dbsize = 0;
-    int nbchangelogs = 0;
+    int nbvlvs = 0;
     int nbsuffixes = 0;
     int nbindexes = 0;
     int nbagmt = 0;
@@ -100,7 +100,7 @@ dbmdb_compute_limits(struct ldbminfo *li)
      */
     if (dbmdb_count_config_entries("(objectClass=nsMappingTree)", &nbsuffixes) ||
         dbmdb_count_config_entries("(objectClass=nsIndex)", &nbsuffixes) ||
-        dbmdb_count_config_entries("(&(objectClass=nsds5Replica)(nsDS5Flags=1))", &nbchangelogs) ||
+        dbmdb_count_config_entries("(objectClass=vlvIndex)", &nbvlvs) ||
         dbmdb_count_config_entries("(objectClass=nsds5replicationagreement)", &nbagmt)) {
         /* error message is already logged */
         return 1;
@@ -120,8 +120,15 @@ dbmdb_compute_limits(struct ldbminfo *li)
 
     info->pagesize = sysconf(_SC_PAGE_SIZE);
     limits->min_readers = config_get_threadnumber() + nbagmt + DBMDB_READERS_MARGIN;
-    /* Default indexes are counted in "nbindexes" so we should always have enough resource to add 1 new suffix */
-    limits->min_dbs = nbsuffixes + nbindexes + nbchangelogs + DBMDB_DBS_MARGIN;
+    /*
+     * For each suffix there are 4 databases instances:
+     *  long-entryrdn, replication_changelog, id2entry and ancestorid
+     * then the indexes and the vlv and vlv cache
+     *
+     * Default indexes are counted in "nbindexes" so we should always have enough
+     *  resource to add 1 new suffix
+     */
+    limits->min_dbs = 4*nbsuffixes + nbindexes + 2*nbvlvs + DBMDB_DBS_MARGIN;
 
     total_space = ((uint64_t)(buf.f_blocks)) * ((uint64_t)(buf.f_bsize));
     avail_space = ((uint64_t)(buf.f_bavail)) * ((uint64_t)(buf.f_bsize));

ldap/servers/slapd/back-ldbm/db-mdb/mdb_import_threads.c

@@ -4280,9 +4280,12 @@ dbmdb_import_init_writer(ImportJob *job, ImportRole_t role)
 void
 dbmdb_free_import_ctx(ImportJob *job)
 {
-    if (job->writer_ctx) {
-        ImportCtx_t *ctx = job->writer_ctx;
-        job->writer_ctx = NULL;
+    ImportCtx_t *ctx = NULL;
+    pthread_mutex_lock(get_import_ctx_mutex());
+    ctx = job->writer_ctx;
+    job->writer_ctx = NULL;
+    pthread_mutex_unlock(get_import_ctx_mutex());
+    if (ctx) {
         pthread_mutex_destroy(&ctx->workerq.mutex);
         pthread_cond_destroy(&ctx->workerq.cv);
         slapi_ch_free((void**)&ctx->workerq.slots);

ldap/servers/slapd/back-ldbm/db-mdb/mdb_instance.c

@@ -287,6 +287,13 @@ int add_dbi(dbi_open_ctx_t *octx, backend *be, const char *fname, int flags)
         slapi_ch_free((void**)&treekey.dbname);
         return octx->rc;
     }
+    if (treekey.dbi >= ctx->dsecfg.max_dbs) {
+        octx->rc = MDB_DBS_FULL;
+        slapi_log_err(SLAPI_LOG_ERR, "add_dbi", "Failed to open database instance %s slots: %d/%d. Error is %d: %s.\n",
+                      treekey.dbname, treekey.dbi, ctx->dsecfg.max_dbs, octx->rc, mdb_strerror(octx->rc));
+        slapi_ch_free((void**)&treekey.dbname);
+        return octx->rc;
+    }
     if (octx->ai && octx->ai->ai_key_cmp_fn) {
 		octx->rc = dbmdb_update_dbi_cmp_fn(ctx, &treekey, octx->ai->ai_key_cmp_fn, octx->txn);
         if (octx->rc) {
@@ -694,6 +701,7 @@ int dbmdb_make_env(dbmdb_ctx_t *ctx, int readOnly, mdb_mode_t mode)
         rc = dbmdb_write_infofile(ctx);
     } else {
         /* No Config ==> read it from info file */
+        ctx->dsecfg = ctx->startcfg;
     }
     if (rc) {
         return rc;

ldap/servers/slapd/back-ldbm/dbimpl.c

@@ -505,7 +505,7 @@ int dblayer_show_statistics(const char *dbimpl_name, const char *dbhome, FILE *f
     li->li_plugin = be->be_database;
     li->li_plugin->plg_name = (char*) "back-ldbm-dbimpl";
     li->li_plugin->plg_libpath = (char*) "libback-ldbm";
-    li->li_directory = (char*)dbhome;
+    li->li_directory = get_li_directory(dbhome);
 
     /* Initialize database plugin */
     rc = dbimpl_setup(li, dbimpl_name);

ldap/servers/slapd/back-ldbm/import.c

@@ -27,6 +27,8 @@
 #define NEED_DN_NORM_SP -25
 #define NEED_DN_NORM_BT -26
 
+pthread_mutex_t import_ctx_mutex = PTHREAD_MUTEX_INITIALIZER; /* Protect agains import context destruction */
+
 
 /********** routines to manipulate the entry fifo **********/
 
@@ -143,6 +145,14 @@ ldbm_back_wire_import(Slapi_PBlock *pb)
 
 /* Threads management */
 
+/* Return the mutex that protects against import context destruction */
+pthread_mutex_t *
+get_import_ctx_mutex()
+{
+    return &import_ctx_mutex;
+}
+
+
 /* tell all the threads to abort */
 void
 import_abort_all(ImportJob *job, int wait_for_them)
@@ -151,7 +161,7 @@ import_abort_all(ImportJob *job, int wait_for_them)
 
     /* tell all the worker threads to abort */
     job->flags |= FLAG_ABORT;
-
+    pthread_mutex_lock(&import_ctx_mutex);
     for (worker = job->worker_list; worker; worker = worker->next)
         worker->command = ABORT;
 
@@ -167,6 +177,7 @@ import_abort_all(ImportJob *job, int wait_for_them)
             }
         }
     }
+    pthread_mutex_unlock(&import_ctx_mutex);
 }