Fix resqueue

src/backend/catalog/system_views.sql

@@ -1224,6 +1224,25 @@ CREATE VIEW pg_resqueue_status AS
              queueholders int4)
             ON (s.queueid = q.oid);
 
+-- Resource queue cumulative statistics view
+CREATE VIEW pg_stat_resqueues AS
+    SELECT
+        q.oid                           AS queueid,
+        q.rsqname                       AS queuename,
+        s.queries_submitted,
+        s.queries_admitted,
+        s.queries_rejected,
+        s.queries_completed,
+        s.elapsed_wait_secs             AS total_wait_time_secs,
+        s.max_wait_secs,
+        s.elapsed_exec_secs             AS total_exec_time_secs,
+        s.max_exec_secs,
+        s.total_cost,
+        s.total_memory_kb,
+        s.stat_reset_timestamp
+    FROM pg_resqueue AS q,
+         pg_stat_get_resqueue_stats(q.oid) AS s;
+
 -- External table views
 
 CREATE VIEW pg_max_external_files AS

src/backend/cdb/dispatcher/cdbdisp_query.c

@@ -526,6 +526,12 @@ cdbdisp_dispatchCommandInternal(DispatchCommandQueryParms *pQueryParms,
 		ThrowErrorData(qeError);
 	}
 
+	/*
+	 * GPDB: Merge relation stats sent by QEs so QD's mod_since_analyze
+	 * stays up to date for autovacuum triggering.
+	 */
+	pgstat_combine_from_qe(pr);
+
 	cdbdisp_returnResults(pr, cdb_pgresults);
 
 	cdbdisp_destroyDispatcherState(ds);

src/backend/executor/execUtils.c

@@ -2144,6 +2144,12 @@ void mppExecutorFinishup(QueryDesc *queryDesc)
 		if (ProcessDispatchResult_hook)
 			ProcessDispatchResult_hook(ds);
 
+		/*
+		 * GPDB: Merge relation stats sent by QEs so QD's mod_since_analyze
+		 * stays up to date for autovacuum triggering.
+		 */
+		pgstat_combine_from_qe(pr);
+
 		/* get num of rows processed from writer QEs. */
 		estate->es_processed +=
 			cdbdisp_sumCmdTuples(pr, primaryWriterSliceIndex);
@@ -2225,6 +2231,12 @@ uint64 mppExecutorWait(QueryDesc *queryDesc)
 										LocallyExecutingSliceIndex(queryDesc->estate),
 										estate->showstatctx);
 		}
+		/*
+		 * GPDB: Merge relation stats sent by QEs so QD's mod_since_analyze
+		 * stays up to date for autovacuum triggering.
+		 */
+		pgstat_combine_from_qe(pr);
+
 		/* get num of rows processed from writer QEs. */
 		es_processed +=
 			cdbdisp_sumCmdTuples(pr, primaryWriterSliceIndex);

src/backend/postmaster/autovacuum.c

@@ -676,16 +676,17 @@ AutoVacLauncherMain(int argc, char *argv[])
  * the database chosen is connectable, the launcher will never select it and the
  * worker will continue to signal for a new launcher.
  */
-#if 0
 	/*
 	 * Even when system is configured to use a different fetch consistency,
 	 * for autovac we always want fresh stats.
 	 */
 	SetConfigOption("stats_fetch_consistency", "none", PGC_SUSET, PGC_S_OVERRIDE);
 
+#if 0
 	/*
-	 * In emergency mode, just start a worker (unless shutdown was requested)
-	 * and go away.
+	 * In GPDB, we only want an autovacuum worker to start once we know
+	 * there is a database to vacuum. Therefore, we never want emergency mode
+	 * to start a worker immediately.
 	 */
 	if (!AutoVacuumingActive())
 	{
@@ -1067,60 +1068,75 @@ rebuild_database_list(Oid newdb)
 	if (OidIsValid(newdb))
 	{
 		avl_dbase  *db;
-		PgStat_StatDBEntry *entry;
 
-		/* only consider this database if it has a pgstat entry */
-		entry = pgstat_fetch_stat_dbentry(newdb);
-		if (entry != NULL)
-		{
-			/* we assume it isn't found because the hash was just created */
-			db = hash_search(dbhash, &newdb, HASH_ENTER, NULL);
+		/*
+		 * In GPDB, include databases even without pgstat entries since
+		 * newly created databases may already need auto-analyze via
+		 * QE→QD pgstat collection.
+		 */
 
-			/* hash_search already filled in the key */
-			db->adl_score = score++;
-			/* next_worker is filled in later */
-		}
+		/* we assume it isn't found because the hash was just created */
+		db = hash_search(dbhash, &newdb, HASH_ENTER, NULL);
+
+		/* hash_search already filled in the key */
+		db->adl_score = score++;
+		/* next_worker is filled in later */
 	}
 
-	/* Now insert the databases from the existing list */
-	dlist_foreach(iter, &DatabaseList)
+	/*
+	 * Get the current list of databases first, so we can cross-reference
+	 * existing DatabaseList entries and exclude dropped databases.
+	 * In GPDB, we include databases even without pgstat entries since
+	 * newly created databases may need auto-analyze via QE→QD pgstat.
+	 */
+	dblist = get_database_list();
+
+	/* Build a set of current database OIDs for quick lookup */
 	{
-		avl_dbase  *avdb = dlist_container(avl_dbase, adl_node, iter.cur);
-		avl_dbase  *db;
-		bool		found;
-		PgStat_StatDBEntry *entry;
+		HASHCTL		oid_hctl;
+		HTAB	   *current_db_oids;
+
+		oid_hctl.keysize = sizeof(Oid);
+		oid_hctl.entrysize = sizeof(Oid);
+		oid_hctl.hcxt = tmpcxt;
+		current_db_oids = hash_create("current db oids", 20, &oid_hctl,
+									  HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
+		foreach(cell, dblist)
+		{
+			avw_dbase  *avdb = lfirst(cell);
+			hash_search(current_db_oids, &(avdb->adw_datid), HASH_ENTER, NULL);
+		}
 
-		/*
-		 * skip databases with no stat entries -- in particular, this gets rid
-		 * of dropped databases
-		 */
-		entry = pgstat_fetch_stat_dbentry(avdb->adl_datid);
-		if (entry == NULL)
-			continue;
+		/* Now insert the databases from the existing list, skipping dropped ones */
+		dlist_foreach(iter, &DatabaseList)
+		{
+			avl_dbase  *avdb = dlist_container(avl_dbase, adl_node, iter.cur);
+			avl_dbase  *db;
+			bool		found;
 
-		db = hash_search(dbhash, &(avdb->adl_datid), HASH_ENTER, &found);
+			/* Skip databases that no longer exist in pg_database */
+			if (!hash_search(current_db_oids, &(avdb->adl_datid), HASH_FIND, NULL))
+				continue;
 
-		if (!found)
-		{
-			/* hash_search already filled in the key */
-			db->adl_score = score++;
-			/* next_worker is filled in later */
+			db = hash_search(dbhash, &(avdb->adl_datid), HASH_ENTER, &found);
+
+			if (!found)
+			{
+				/* hash_search already filled in the key */
+				db->adl_score = score++;
+				/* next_worker is filled in later */
+			}
 		}
+
+		hash_destroy(current_db_oids);
 	}
 
 	/* finally, insert all qualifying databases not previously inserted */
-	dblist = get_database_list();
 	foreach(cell, dblist)
 	{
 		avw_dbase  *avdb = lfirst(cell);
 		avl_dbase  *db;
 		bool		found;
-		PgStat_StatDBEntry *entry;
-
-		/* only consider databases with a pgstat entry */
-		entry = pgstat_fetch_stat_dbentry(avdb->adw_datid);
-		if (entry == NULL)
-			continue;
 
 		db = hash_search(dbhash, &(avdb->adw_datid), HASH_ENTER, &found);
 		/* only update the score if the database was not already on the hash */
@@ -1328,11 +1344,12 @@ do_start_worker(void)
 		tmp->adw_entry = pgstat_fetch_stat_dbentry(tmp->adw_datid);
 
 		/*
-		 * Skip a database with no pgstat entry; it means it hasn't seen any
-		 * activity.
+		 * Don't skip databases without pgstat entries.  In GPDB, a newly
+		 * created database may already have tables needing auto-analyze
+		 * (via QE→QD pgstat) before the database-level pgstat entry is
+		 * flushed to shared memory.  Treat them as candidates with the
+		 * oldest last_autovac_time so they get visited promptly.
 		 */
-		if (!tmp->adw_entry)
-			continue;
 
 		/*
 		 * Also, skip a database that appears on the database list as having
@@ -1367,11 +1384,13 @@ do_start_worker(void)
 			continue;
 
 		/*
-		 * Remember the db with oldest autovac time.  (If we are here, both
-		 * tmp->entry and db->entry must be non-null.)
+		 * Remember the db with oldest autovac time.  A database without a
+		 * pgstat entry is treated as having last_autovac_time = 0, giving
+		 * it the highest priority.
 		 */
 		if (avdb == NULL ||
-			tmp->adw_entry->last_autovac_time < avdb->adw_entry->last_autovac_time)
+			(tmp->adw_entry ? tmp->adw_entry->last_autovac_time : 0) <
+			(avdb->adw_entry ? avdb->adw_entry->last_autovac_time : 0))
 			avdb = tmp;
 	}
 

src/backend/tcop/postgres.c

@@ -1498,6 +1498,14 @@ exec_mpp_query(const char *query_string,
 
 		PortalDrop(portal, false);
 
+		/*
+		 * GPDB: Send pending relation stats to QD before closing the
+		 * transaction.  The stats are in pgStatXactStack (transaction-level
+		 * counts); finish_xact_command() will call AtEOXact_PgStat() which
+		 * NULLs pgStatXactStack, so we must capture the stats first.
+		 */
+		pgstat_send_qd_tabstats();
+
 		/*
 		 * Close down transaction statement before reporting command-complete.
 		 * This is so that any end-of-transaction errors are reported before

src/backend/utils/activity/Makefile

@@ -13,6 +13,9 @@ subdir = src/backend/utils/activity
 top_builddir = ../../../..
 include $(top_builddir)/src/Makefile.global
 
+# GPDB: needed for libpq-int.h (PGExtraType, pg_result struct)
+override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
+
 OBJS = \
 	backend_progress.o \
 	backend_status.o \
@@ -25,6 +28,7 @@ OBJS = \
 	pgstat_io.o \
 	pgstat_relation.o \
 	pgstat_replslot.o \
+	pgstat_resqueue.o \
 	pgstat_shmem.o \
 	pgstat_slru.o \
 	pgstat_subscription.o \