6 files changed, 77 insertions, 1 deletions
diff --git a/src/backend/access/gin/ginfast.c b/src/backend/access/gin/ginfast.c
index 681ce098144..09f41f55ac7 100644
--- a/src/backend/access/gin/ginfast.c
+++ b/src/backend/access/gin/ginfast.c
@@ -20,10 +20,13 @@
 
 #include "access/gin_private.h"
 #include "access/xloginsert.h"
+#include "access/xlog.h"
 #include "commands/vacuum.h"
+#include "catalog/pg_am.h"
 #include "miscadmin.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"
+#include "utils/acl.h"
 #include "storage/indexfsm.h"
 
 /* GUC parameter */
@@ -958,3 +961,52 @@ ginInsertCleanup(GinState *ginstate,
 	MemoryContextSwitchTo(oldCtx);
 	MemoryContextDelete(opCtx);
 }
+
+/*
+ * SQL-callable function to clean the insert pending list
+ */
+Datum
+gin_clean_pending_list(PG_FUNCTION_ARGS)
+{
+	Oid			indexoid = PG_GETARG_OID(0);
+	Relation	indexRel = index_open(indexoid, AccessShareLock);
+	IndexBulkDeleteResult stats;
+	GinState	ginstate;
+
+	if (RecoveryInProgress())
+ 		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("recovery is in progress"),
+				 errhint("GIN pending list cannot be cleaned up during recovery.")));
+
+	/* Must be a GIN index */
+	if (indexRel->rd_rel->relkind != RELKIND_INDEX ||
+		indexRel->rd_rel->relam != GIN_AM_OID)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is not a GIN index",
+						RelationGetRelationName(indexRel))));
+
+	/*
+	 * Reject attempts to read non-local temporary relations; we would be
+	 * likely to get wrong data since we have no visibility into the owning
+	 * session's local buffers.
+	 */
+	if (RELATION_IS_OTHER_TEMP(indexRel))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+			   errmsg("cannot access temporary indexes of other sessions")));
+
+	/* User must own the index (comparable to privileges needed for VACUUM) */
+	if (!pg_class_ownercheck(indexoid, GetUserId()))
+		aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
+					   RelationGetRelationName(indexRel));
+
+	memset(&stats, 0, sizeof(stats));
+	initGinState(&ginstate, indexRel);
+	ginInsertCleanup(&ginstate, true, &stats);
+
+	index_close(indexRel, AccessShareLock);
+
+	PG_RETURN_INT64((int64) stats.pages_deleted);
+}
diff --git a/src/include/access/gin_private.h b/src/include/access/gin_private.h
index 695959c5b18..d2ea58832ce 100644
--- a/src/include/access/gin_private.h
+++ b/src/include/access/gin_private.h
@@ -881,6 +881,9 @@ extern void ginFreeScanKeys(GinScanOpaque so);
 /* ginget.c */
 extern int64 gingetbitmap(IndexScanDesc scan, TIDBitmap *tbm);
 
+/* ginfast.c */
+extern Datum gin_clean_pending_list(PG_FUNCTION_ARGS);
+
 /* ginlogic.c */
 extern void ginInitConsistentFunction(GinState *ginstate, GinScanKey key);
 
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 1f18806fb52..5c480b7d3ab 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201601271
+#define CATALOG_VERSION_NO	201601281
 
 #endif
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 3a066abc82f..ba8760b37d4 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -4517,6 +4517,8 @@ DATA(insert OID = 3087 (  gin_extract_tsquery	PGNSP PGUID 12 1 0 0 0 f f f f t f
 DESCR("GIN tsvector support (obsolete)");
 DATA(insert OID = 3088 (  gin_tsquery_consistent PGNSP PGUID 12 1 0 0 0 f f f f t f i s 6 0 16 "2281 21 3615 23 2281 2281" _null_ _null_ _null_ _null_ _null_ gin_tsquery_consistent_6args _null_ _null_ _null_ ));
 DESCR("GIN tsvector support (obsolete)");
+DATA(insert OID = 3789 (  gin_clean_pending_list PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 20 "2205" _null_ _null_ _null_ _null_ _null_ gin_clean_pending_list _null_ _null_ _null_ ));
+DESCR("clean up GIN pending list");
 
 DATA(insert OID = 3662 (  tsquery_lt			PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "3615 3615" _null_ _null_ _null_ _null_ _null_ tsquery_lt _null_ _null_ _null_ ));
 DATA(insert OID = 3663 (  tsquery_le			PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "3615 3615" _null_ _null_ _null_ _null_ _null_ tsquery_le _null_ _null_ _null_ ));
diff --git a/src/test/regress/expected/gin.out b/src/test/regress/expected/gin.out
index c015fe7861a..cc7601c6677 100644
--- a/src/test/regress/expected/gin.out
+++ b/src/test/regress/expected/gin.out
@@ -8,7 +8,20 @@ create table gin_test_tbl(i int4[]);
 create index gin_test_idx on gin_test_tbl using gin (i) with (fastupdate = on);
 insert into gin_test_tbl select array[1, 2, g] from generate_series(1, 20000) g;
 insert into gin_test_tbl select array[1, 3, g] from generate_series(1, 1000) g;
+select gin_clean_pending_list('gin_test_idx')>10 as many; -- flush the fastupdate buffers
+ many 
+------
+ t
+(1 row)
+
+insert into gin_test_tbl select array[3, 1, g] from generate_series(1, 1000) g;
 vacuum gin_test_tbl; -- flush the fastupdate buffers
+select gin_clean_pending_list('gin_test_idx'); -- nothing to flush
+ gin_clean_pending_list 
+------------------------
+                      0
+(1 row)
+
 -- Test vacuuming
 delete from gin_test_tbl where i @> array[2];
 vacuum gin_test_tbl;
diff --git a/src/test/regress/sql/gin.sql b/src/test/regress/sql/gin.sql
index 4b35560036a..31890b46d8c 100644
--- a/src/test/regress/sql/gin.sql
+++ b/src/test/regress/sql/gin.sql
@@ -10,8 +10,14 @@ create index gin_test_idx on gin_test_tbl using gin (i) with (fastupdate = on);
 insert into gin_test_tbl select array[1, 2, g] from generate_series(1, 20000) g;
 insert into gin_test_tbl select array[1, 3, g] from generate_series(1, 1000) g;
 
+select gin_clean_pending_list('gin_test_idx')>10 as many; -- flush the fastupdate buffers
+
+insert into gin_test_tbl select array[3, 1, g] from generate_series(1, 1000) g;
+
 vacuum gin_test_tbl; -- flush the fastupdate buffers
 
+select gin_clean_pending_list('gin_test_idx'); -- nothing to flush
+
 -- Test vacuuming
 delete from gin_test_tbl where i @> array[2];
 vacuum gin_test_tbl;