From: Robert Haas <rhaas@postgresql.org>
Date: Thu, 15 Sep 2016 13:22:52 +0000 (-0400)
Subject: pg_buffercache: Allow huge allocations.
X-Git-Tag: REL9_6_0~26
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=bea38f34a4e601d2ea803a3a6d6b90ee0fe2d2b6;p=postgresql

pg_buffercache: Allow huge allocations.

Otherwise, users who have configured shared_buffers >= 256GB won't
be able to use this module.  There probably aren't many of those, but
it doesn't hurt anything to fix it so that it works.

Backpatch to 9.4, where MemoryContextAllocHuge was introduced.  The
same problem exists in older branches, but there's no easy way to
fix it there.

KaiGai Kohei
---

diff --git a/contrib/pg_buffercache/pg_buffercache_pages.c b/contrib/pg_buffercache/pg_buffercache_pages.c
index 17b4b6fa6f..da13bde359 100644
--- a/contrib/pg_buffercache/pg_buffercache_pages.c
+++ b/contrib/pg_buffercache/pg_buffercache_pages.c
@@ -124,7 +124,9 @@ pg_buffercache_pages(PG_FUNCTION_ARGS)
 		fctx->tupdesc = BlessTupleDesc(tupledesc);
 
 		/* Allocate NBuffers worth of BufferCachePagesRec records. */
-		fctx->record = (BufferCachePagesRec *) palloc(sizeof(BufferCachePagesRec) * NBuffers);
+		fctx->record = (BufferCachePagesRec *)
+			MemoryContextAllocHuge(CurrentMemoryContext,
+								   sizeof(BufferCachePagesRec) * NBuffers);
 
 		/* Set max calls and remember the user function context. */
 		funcctx->max_calls = NBuffers;