3 files changed, 45 insertions, 1 deletions
diff --git a/src/backend/utils/adt/misc.c b/src/backend/utils/adt/misc.c
index 1ec7f32470a..7dcecb2f0f6 100644
--- a/src/backend/utils/adt/misc.c
+++ b/src/backend/utils/adt/misc.c
@@ -982,3 +982,23 @@ pg_current_logfile_1arg(PG_FUNCTION_ARGS)
 {
 	return pg_current_logfile(fcinfo);
 }
+
+/*
+ * SQL wrapper around RelationGetReplicaIndex().
+ */
+Datum
+pg_get_replica_identity_index(PG_FUNCTION_ARGS)
+{
+	Oid			reloid = PG_GETARG_OID(0);
+	Oid			idxoid;
+	Relation	rel;
+
+	rel = heap_open(reloid, AccessShareLock);
+	idxoid = RelationGetReplicaIndex(rel);
+	heap_close(rel, AccessShareLock);
+
+	if (OidIsValid(idxoid))
+		PG_RETURN_OID(idxoid);
+	else
+		PG_RETURN_NULL();
+}
diff --git a/src/backend/utils/cache/syscache.c b/src/backend/utils/cache/syscache.c
index b1c0b4b1be1..d5a376406fe 100644
--- a/src/backend/utils/cache/syscache.c
+++ b/src/backend/utils/cache/syscache.c
@@ -62,6 +62,7 @@
 #include "catalog/pg_replication_origin.h"
 #include "catalog/pg_statistic.h"
 #include "catalog/pg_subscription.h"
+#include "catalog/pg_subscription_rel.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_transform.h"
 #include "catalog/pg_ts_config.h"
@@ -693,7 +694,7 @@ static const struct cachedesc cacheinfo[] = {
 		64
 	},
 	{PublicationRelRelationId,		/* PUBLICATIONRELMAP */
-		PublicationRelMapIndexId,
+		PublicationRelPrrelidPrpubidIndexId,
 		2,
 		{
 			Anum_pg_publication_rel_prrelid,
@@ -758,6 +759,17 @@ static const struct cachedesc cacheinfo[] = {
 		},
 		4
 	},
+	{SubscriptionRelRelationId,		/* SUBSCRIPTIONRELMAP */
+		SubscriptionRelSrrelidSrsubidIndexId,
+		2,
+		{
+			Anum_pg_subscription_rel_srrelid,
+			Anum_pg_subscription_rel_srsubid,
+			0,
+			0
+		},
+		64
+	},
 	{TableSpaceRelationId,		/* TABLESPACEOID */
 		TablespaceOidIndexId,
 		1,
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 4feb26aa7a0..291bf7631db 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -2498,6 +2498,18 @@ static struct config_int ConfigureNamesInt[] =
 	},
 
 	{
+		{"max_sync_workers_per_subscription",
+			PGC_SIGHUP,
+			RESOURCES_ASYNCHRONOUS,
+			gettext_noop("Maximum number of table synchronization workers per subscription."),
+			NULL,
+		},
+		&max_sync_workers_per_subscription,
+		2, 0, MAX_BACKENDS,
+		NULL, NULL, NULL
+	},
+
+	{
 		{"log_rotation_age", PGC_SIGHUP, LOGGING_WHERE,
 			gettext_noop("Automatic log file rotation will occur after N minutes."),
 			NULL,