copy_nohints.v357.patch

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index c910863..3899282 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -2056,6 +2056,17 @@ heap_prepare_insert(Relation relation, HeapTuple tup, TransactionId xid,
 	tup->t_tableOid = RelationGetRelid(relation);
 
 	/*
+	 * If we are inserting into a new relation invisible as yet to other
+	 * backends and our session has no prior snapshots and no ready portals
+	 * then we can also set the hint bit for the rows we are inserting. The
+	 * last two restrictions ensure that HeapTupleSatisfiesMVCC() gives
+	 * the right answer if the current transaction inspects the data after
+	 * we load it.
+	 */
+	if (options & HEAP_INSERT_HINT_XMIN)
+		tup->t_data->t_infomask |= HEAP_XMIN_COMMITTED;
+
+	/*
 	 * If the new tuple is too big for storage or contains already toasted
 	 * out-of-line attributes from some other relation, invoke the toaster.
 	 */
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 110480f..6a60eb8 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -43,6 +43,7 @@
 #include "utils/builtins.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/rel.h"
 #include "utils/snapmgr.h"
 
@@ -1922,6 +1923,10 @@ CopyFrom(CopyState cstate)
 		hi_options |= HEAP_INSERT_SKIP_FSM;
 		if (!XLogIsNeeded())
 			hi_options |= HEAP_INSERT_SKIP_WAL;
+
+		if (ThereAreNoPriorRegisteredSnapshots() &&
+			ThereAreNoReadyPortals())
+			hi_options |= HEAP_INSERT_HINT_XMIN;
 	}
 
 	/*
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index cfb73c1..24075db 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -1055,3 +1055,22 @@ pg_cursor(PG_FUNCTION_ARGS)
 
 	return (Datum) 0;
 }
+
+bool
+ThereAreNoReadyPortals(void)
+{
+	HASH_SEQ_STATUS status;
+	PortalHashEnt *hentry;
+
+	hash_seq_init(&status, PortalHashTable);
+
+	while ((hentry = (PortalHashEnt *) hash_seq_search(&status)) != NULL)
+	{
+		Portal		portal = hentry->portal;
+
+		if (portal->status == PORTAL_READY)
+			return false;
+	}
+
+	return true;
+}
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
index 5aebbd1..5d9e3bf 100644
--- a/src/backend/utils/time/snapmgr.c
+++ b/src/backend/utils/time/snapmgr.c
@@ -1183,3 +1183,12 @@ DeleteAllExportedSnapshotFiles(void)
 
 	FreeDir(s_dir);
 }
+
+bool
+ThereAreNoPriorRegisteredSnapshots(void)
+{
+	if (RegisteredSnapshots <= 1)
+		return true;
+
+	return false;
+}
diff --git a/src/backend/utils/time/tqual.c b/src/backend/utils/time/tqual.c
index 31791a7..a2e5524 100644
--- a/src/backend/utils/time/tqual.c
+++ b/src/backend/utils/time/tqual.c
@@ -1256,7 +1256,18 @@ XidInMVCCSnapshot(TransactionId xid, Snapshot snapshot)
 	if (TransactionIdPrecedes(xid, snapshot->xmin))
 		return false;
 	/* Any xid >= xmax is in-progress */
-	if (TransactionIdFollowsOrEquals(xid, snapshot->xmax))
+	if (TransactionIdFollows(xid, snapshot->xmax))
+		return true;
+	/*
+	 * Make sure current xid is never thought to be in progress on tuples
+	 * that are already marked as committed - for use in bulk COPY etc..
+	 * We never included the current xid in snapshots, but if it happens
+	 * to be xmax it could still be returned as in-progress.
+	 */
+	if (TransactionIdIsCurrentTransactionId(xid))
+		return false;
+	/* All non-current xids >= xmax are seen as still running */
+	if (xid == snapshot->xmax)
 		return true;
 
 	/*
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index fa38803..0381785 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -26,6 +26,7 @@
 /* "options" flag bits for heap_insert */
 #define HEAP_INSERT_SKIP_WAL	0x0001
 #define HEAP_INSERT_SKIP_FSM	0x0002
+#define HEAP_INSERT_HINT_XMIN	0x0004
 
 typedef struct BulkInsertStateData *BulkInsertState;
 
diff --git a/src/include/utils/portal.h b/src/include/utils/portal.h
index 4833942..bd2b133 100644
--- a/src/include/utils/portal.h
+++ b/src/include/utils/portal.h
@@ -219,5 +219,6 @@ extern void PortalDefineQuery(Portal portal,
 extern Node *PortalListGetPrimaryStmt(List *stmts);
 extern void PortalCreateHoldStore(Portal portal);
 extern void PortalHashTableDeleteAll(void);
+extern bool ThereAreNoReadyPortals(void);
 
 #endif   /* PORTAL_H */
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index f195981..789b72e 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -46,5 +46,6 @@ extern Datum pg_export_snapshot(PG_FUNCTION_ARGS);
 extern void ImportSnapshot(const char *idstr);
 extern bool XactHasExportedSnapshots(void);
 extern void DeleteAllExportedSnapshotFiles(void);
+extern bool ThereAreNoPriorRegisteredSnapshots(void);
 
 #endif   /* SNAPMGR_H */