- Synced with main

- Removed maintenance_management_database GUC and logic

src/backend/distributed/connection/connection_management.c

@@ -360,9 +360,7 @@ StartNodeUserDatabaseConnection(uint32 flags, const char *hostname, int32 port,
 		MultiConnection *connection = FindAvailableConnection(entry->connections, flags);
 		if (connection)
 		{
-            if ((flags & REQUIRE_MAINTENANCE_CONNECTION) &&
+            if (flags & REQUIRE_MAINTENANCE_CONNECTION)
-                IsMaintenanceDaemon &&
-                !IsMaintenanceManagementDatabase(MyDatabaseId))
             {
                 // Maintenance database may have changed, so cached connection should be closed
                 connection->forceCloseAtTransactionEnd = true;
@@ -446,10 +444,7 @@ StartNodeUserDatabaseConnection(uint32 flags, const char *hostname, int32 port,
     else if (flags & REQUIRE_MAINTENANCE_CONNECTION)
     {
         connection->useForMaintenanceOperations = true;
-        if (IsMaintenanceDaemon && !IsMaintenanceManagementDatabase(MyDatabaseId))
+        connection->forceCloseAtTransactionEnd = true;
-        {
-            connection->forceCloseAtTransactionEnd = true;
-        }
     }
 
 	/* fully initialized the connection, record it */

src/backend/distributed/shared_library_init.c

@@ -2705,17 +2705,6 @@ RegisterCitusConfigVariables(void)
 		GUC_STANDARD,
 		NULL, NULL, NULL);
 
-    DefineCustomStringVariable(
-            "citus.maintenance_management_database",
-            gettext_noop("Database for cluster-wide maintenance operations across all databases"),
-            gettext_noop("It should be enabled when there are more than "
-                         "one database with Citus in a cluster."),
-            &MaintenanceManagementDatabase,
-            "",
-            PGC_SIGHUP,
-            GUC_STANDARD,
-            NULL, NULL, NULL);
-
 	/* warn about config items in the citus namespace that are not registered above */
 	EmitWarningsOnPlaceholders("citus");
 

src/backend/distributed/utils/maintenanced.c

@@ -718,27 +718,24 @@ CitusMaintenanceDaemonMain(Datum main_arg)
             InvalidateMetadataSystemCache();
             StartTransactionCommand();
 
-
+            /*
-            if ((strcmp(GetMaintenanceManagementDatabase(), "") == 0 || IsMaintenanceManagementDatabase(databaseOid)))
+             * We skip the deadlock detection if citus extension
+             * is not accessible.
+             *
+             * Similarly, we skip to run the deadlock checks if
+             * there exists any version mismatch or the extension
+             * is not fully created yet.
+             */
+            if (!LockCitusExtension())
             {
-                /*
+                ereport(DEBUG1, (errmsg("could not lock the citus extension, "
-                 * We skip the deadlock detection if citus extension
+                                        "skipping deadlock detection")));
-                 * is not accessible.
-                 *
-                 * Similarly, we skip to run the deadlock checks if
-                 * there exists any version mismatch or the extension
-                 * is not fully created yet.
-                 */
-                if (!LockCitusExtension())
-                {
-                    ereport(DEBUG1, (errmsg("could not lock the citus extension, "
-                                            "skipping deadlock detection")));
-                }
-                else if (CheckCitusVersion(DEBUG1) && CitusHasBeenLoaded())
-                {
-                    foundDeadlock = CheckForDistributedDeadlocks();
-                }
             }
+            else if (CheckCitusVersion(DEBUG1) && CitusHasBeenLoaded())
+            {
+                foundDeadlock = CheckForDistributedDeadlocks();
+            }
+
 
 			CommitTransactionCommand();
 
@@ -1237,35 +1234,3 @@ MetadataSyncTriggeredCheckAndReset(MaintenanceDaemonDBData *dbData)
 	return metadataSyncTriggered;
 }
 
-char
-*GetMaintenanceManagementDatabase(void)
-{
-    char *result = MaintenanceManagementDatabase;
-    /* If MaintenanceManagementDatabase is not set, all maintenance daemons are considered independent */
-    if (strcmp(MaintenanceManagementDatabase, "") != 0)
-    {
-        Oid maintenanceDatabaseOid = get_database_oid(MaintenanceManagementDatabase, true);
-        if (!maintenanceDatabaseOid)
-        {
-            ereport(WARNING, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-                    errmsg("Database \"%s\" doesn't exists, please check the citus.maintenance_management_database parameter. "
-                           "Applying a default value instead.",
-                           MaintenanceManagementDatabase)));
-            result = "";
-        }
-    }
-    return result;
-}
-
-bool
-IsMaintenanceManagementDatabase(Oid databaseOid)
-{
-    if (strcmp(GetMaintenanceManagementDatabase(), "") == 0)
-    {
-        /* If MaintenanceManagementDatabase is not set, all maintenance daemons are considered independent */
-        return false;
-    }
-    Oid maintenanceDatabaseOid = get_database_oid(MaintenanceManagementDatabase, true);
-    return maintenanceDatabaseOid == databaseOid;
-}
-

src/test/regress/expected/multi_maintenance_multiple_databases.out

@@ -1,9 +1,5 @@
 -- This test verfies a behavioir of maintenance daemon in multi-database environment
--- It checks two things:
+-- It checks that distributed deadlock detection and 2PC transaction recovery should respect the citus.shared_pool_size_maintenance_quota.
--- 1. Maintenance daemons should not cache connections, except the one for the citus.maintenance_management_database
--- 2. 2PC transaction recovery should respect the citus.shared_pool_size_maintenance_quota
--- 2. Distributed deadlock detection should run only on citus.maintenance_management_database.
---
 -- To do that, it created 100 databases and syntactically generates distributed transactions in various states there.
 SELECT $definition$
        ALTER SYSTEM SET citus.recover_2pc_interval TO '-1';
@@ -14,7 +10,6 @@ SELECT $definition$
 SELECT $deinition$
 ALTER SYSTEM SET citus.recover_2pc_interval TO '5s';
 ALTER SYSTEM RESET citus.distributed_deadlock_detection_factor;
-ALTER SYSTEM SET citus.maintenance_management_database = 'regression';
 SELECT pg_reload_conf();
 $deinition$ AS turn_on_maintenance
 \gset
@@ -284,7 +279,7 @@ WHERE datname LIKE 'db%';
  t
 (1 row)
 
-SELECT count(*) BETWEEN 1 AND 3 AS cached_connections_after_recovery_coordinator_test
+SELECT count(*) = 0 AS cached_connections_after_recovery_coordinator_test
 FROM pg_stat_activity
 WHERE state = 'idle'
   AND now() - backend_start > '5 seconds'::interval;
@@ -303,7 +298,7 @@ WHERE gid LIKE 'citus_0_1234_4_0_%'
  t
 (1 row)
 
-SELECT count(*) BETWEEN 1 AND 3 AS cached_connections_after_recovery_worker_1_test
+SELECT count(*) = 0 AS cached_connections_after_recovery_worker_1_test
 FROM pg_stat_activity
 WHERE state = 'idle'
   AND now() - backend_start > '5 seconds'::interval;
@@ -322,7 +317,7 @@ WHERE gid LIKE 'citus_0_1234_4_0_%'
  t
 (1 row)
 
-SELECT count(*) BETWEEN 1 AND 3 AS cached_connections_after_recovery_worker_2_test
+SELECT count(*) = 0 AS cached_connections_after_recovery_worker_2_test
 FROM pg_stat_activity
 WHERE state = 'idle'
   AND now() - backend_start > '5 seconds'::interval;
@@ -336,7 +331,6 @@ WHERE state = 'idle'
 SELECT $definition$
        ALTER SYSTEM RESET citus.recover_2pc_interval;
        ALTER SYSTEM RESET citus.distributed_deadlock_detection_factor;
-       ALTER SYSTEM RESET citus.maintenance_management_database;
        SELECT pg_reload_conf();
 
        DO
@@ -500,3 +494,5 @@ SELECT $definition$
      0
 (1 row)
 
+\c - - - :master_port
+DROP EXTENSION IF EXISTS dblink;

src/test/regress/sql/multi_maintenance_multiple_databases.sql

@@ -1,9 +1,5 @@
 -- This test verfies a behavioir of maintenance daemon in multi-database environment
--- It checks two things:
+-- It checks that distributed deadlock detection and 2PC transaction recovery should respect the citus.shared_pool_size_maintenance_quota.
--- 1. Maintenance daemons should not cache connections, except the one for the citus.maintenance_management_database
--- 2. 2PC transaction recovery should respect the citus.shared_pool_size_maintenance_quota
--- 2. Distributed deadlock detection should run only on citus.maintenance_management_database.
---
 -- To do that, it created 100 databases and syntactically generates distributed transactions in various states there.
 
 SELECT $definition$
@@ -16,7 +12,6 @@ SELECT $definition$
 SELECT $deinition$
 ALTER SYSTEM SET citus.recover_2pc_interval TO '5s';
 ALTER SYSTEM RESET citus.distributed_deadlock_detection_factor;
-ALTER SYSTEM SET citus.maintenance_management_database = 'regression';
 SELECT pg_reload_conf();
 $deinition$ AS turn_on_maintenance
 \gset
@@ -245,7 +240,7 @@ FROM pg_database,
             $statement$) AS t(groupid integer, gid text)
 WHERE datname LIKE 'db%';
 
-SELECT count(*) BETWEEN 1 AND 3 AS cached_connections_after_recovery_coordinator_test
+SELECT count(*) = 0 AS cached_connections_after_recovery_coordinator_test
 FROM pg_stat_activity
 WHERE state = 'idle'
   AND now() - backend_start > '5 seconds'::interval;
@@ -257,7 +252,7 @@ FROM pg_prepared_xacts
 WHERE gid LIKE 'citus_0_1234_4_0_%'
    OR gid LIKE 'citus_0_should_be_forgotten_%';
 
-SELECT count(*) BETWEEN 1 AND 3 AS cached_connections_after_recovery_worker_1_test
+SELECT count(*) = 0 AS cached_connections_after_recovery_worker_1_test
 FROM pg_stat_activity
 WHERE state = 'idle'
   AND now() - backend_start > '5 seconds'::interval;
@@ -269,7 +264,7 @@ FROM pg_prepared_xacts
 WHERE gid LIKE 'citus_0_1234_4_0_%'
    OR gid LIKE 'citus_0_should_be_forgotten_%';
 
-SELECT count(*) BETWEEN 1 AND 3 AS cached_connections_after_recovery_worker_2_test
+SELECT count(*) = 0 AS cached_connections_after_recovery_worker_2_test
 FROM pg_stat_activity
 WHERE state = 'idle'
   AND now() - backend_start > '5 seconds'::interval;
@@ -282,7 +277,6 @@ WHERE state = 'idle'
 SELECT $definition$
        ALTER SYSTEM RESET citus.recover_2pc_interval;
        ALTER SYSTEM RESET citus.distributed_deadlock_detection_factor;
-       ALTER SYSTEM RESET citus.maintenance_management_database;
        SELECT pg_reload_conf();
 
        DO
@@ -421,3 +415,7 @@ SELECT $definition$
 \c - - - :worker_2_port
 
 :cleanup
+
+\c - - - :master_port
+
+DROP EXTENSION IF EXISTS dblink;