Properly set relpersistence for fake relcache entries.

This can result in buffers failing to be properly flushed at
checkpoint time, leading to data loss.

Report, diagnosis, and patch by Jeff Davis.

diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c
index 6ddcc59b37a45941fd17f8e0b7d3ff0976b346e0..5676120a86310fb167de380810cc738a60397f43 100644 (file)
--- a/src/backend/access/transam/xlogutils.c
+++ b/src/backend/access/transam/xlogutils.c
@@ -394,6 +394,8 @@ CreateFakeRelcacheEntry(RelFileNode rnode)
        FakeRelCacheEntry fakeentry;
        Relation        rel;
 
+       Assert(InRecovery);
+
        /* Allocate the Relation struct and all related space in one block. */
        fakeentry = palloc0(sizeof(FakeRelCacheEntryData));
        rel = (Relation) fakeentry;
@@ -403,6 +405,9 @@ CreateFakeRelcacheEntry(RelFileNode rnode)
        /* We will never be working with temp rels during recovery */
        rel->rd_backend = InvalidBackendId;
 
+       /* It must be a permanent table if we're in recovery. */
+       rel->rd_rel->relpersistence = RELPERSISTENCE_PERMANENT;
+
        /* We don't know the name of the relation; use relfilenode instead */
        sprintf(RelationGetRelationName(rel), "%u", rnode.relNode);
 

diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index dba19ebc6d350b400be5eacbbe76e747bec2a77a..ff92360155d0dec44559389523e5a0f37b7e36a8 100644 (file)
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -271,6 +271,8 @@ ReadBufferWithoutRelcache(RelFileNode rnode, ForkNumber forkNum,
 
        SMgrRelation smgr = smgropen(rnode, InvalidBackendId);
 
+       Assert(InRecovery);
+
        return ReadBuffer_common(smgr, RELPERSISTENCE_PERMANENT, forkNum, blockNum,
                                                         mode, strategy, &hit);
 }