DropRelFileNodeBuffers failed to fix the state of the lookup hash table

that was added to localbuf.c in 8.1; therefore, applying it to a temp table
left corrupt lookup state in memory.  The only case where this had a
significant chance of causing problems was an ON COMMIT DELETE ROWS temp
table; the other possible paths left bogus state that was unlikely to
be used again.  Per report from Csaba Nagy.
This commit is contained in:
Tom Lane 2005-11-17 17:42:02 +00:00
parent 84bb3876bc
commit c859308aba
3 changed files with 54 additions and 23 deletions

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.198 2005/10/27 17:07:58 tgl Exp $
* $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.199 2005/11/17 17:42:02 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1384,34 +1384,17 @@ DropRelFileNodeBuffers(RelFileNode rnode, bool istemp,
BlockNumber firstDelBlock)
{
int i;
volatile BufferDesc *bufHdr;
if (istemp)
{
for (i = 0; i < NLocBuffer; i++)
{
bufHdr = &LocalBufferDescriptors[i];
if (RelFileNodeEquals(bufHdr->tag.rnode, rnode) &&
bufHdr->tag.blockNum >= firstDelBlock)
{
if (LocalRefCount[i] != 0)
elog(ERROR, "block %u of %u/%u/%u is still referenced (local %u)",
bufHdr->tag.blockNum,
bufHdr->tag.rnode.spcNode,
bufHdr->tag.rnode.dbNode,
bufHdr->tag.rnode.relNode,
LocalRefCount[i]);
CLEAR_BUFFERTAG(bufHdr->tag);
bufHdr->flags = 0;
bufHdr->usage_count = 0;
}
}
DropRelFileNodeLocalBuffers(rnode, firstDelBlock);
return;
}
for (i = 0; i < NBuffers; i++)
{
bufHdr = &BufferDescriptors[i];
volatile BufferDesc *bufHdr = &BufferDescriptors[i];
LockBufHdr(bufHdr);
if (RelFileNodeEquals(bufHdr->tag.rnode, rnode) &&
bufHdr->tag.blockNum >= firstDelBlock)

View File

@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.70 2005/10/15 02:49:25 momjian Exp $
* $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.71 2005/11/17 17:42:02 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -241,6 +241,52 @@ WriteLocalBuffer(Buffer buffer, bool release)
}
}
/*
* DropRelFileNodeLocalBuffers
* This function removes from the buffer pool all the pages of the
* specified relation that have block numbers >= firstDelBlock.
* (In particular, with firstDelBlock = 0, all pages are removed.)
* Dirty pages are simply dropped, without bothering to write them
* out first. Therefore, this is NOT rollback-able, and so should be
* used only with extreme caution!
*
* See DropRelFileNodeBuffers in bufmgr.c for more notes.
*/
void
DropRelFileNodeLocalBuffers(RelFileNode rnode, BlockNumber firstDelBlock)
{
int i;
for (i = 0; i < NLocBuffer; i++)
{
BufferDesc *bufHdr = &LocalBufferDescriptors[i];
LocalBufferLookupEnt *hresult;
if ((bufHdr->flags & BM_TAG_VALID) &&
RelFileNodeEquals(bufHdr->tag.rnode, rnode) &&
bufHdr->tag.blockNum >= firstDelBlock)
{
if (LocalRefCount[i] != 0)
elog(ERROR, "block %u of %u/%u/%u is still referenced (local %u)",
bufHdr->tag.blockNum,
bufHdr->tag.rnode.spcNode,
bufHdr->tag.rnode.dbNode,
bufHdr->tag.rnode.relNode,
LocalRefCount[i]);
/* Remove entry from hashtable */
hresult = (LocalBufferLookupEnt *)
hash_search(LocalBufHash, (void *) &bufHdr->tag,
HASH_REMOVE, NULL);
if (!hresult) /* shouldn't happen */
elog(ERROR, "local buffer hash table corrupted");
/* Mark buffer invalid */
CLEAR_BUFFERTAG(bufHdr->tag);
bufHdr->flags = 0;
bufHdr->usage_count = 0;
}
}
}
/*
* InitLocalBuffers -
* init the local buffer cache. Since most queries (esp. multi-user ones)

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@ -8,7 +8,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/storage/buf_internals.h,v 1.81 2005/10/15 02:49:46 momjian Exp $
* $PostgreSQL: pgsql/src/include/storage/buf_internals.h,v 1.82 2005/11/17 17:42:02 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -198,6 +198,8 @@ extern void BufTableDelete(BufferTag *tagPtr);
extern BufferDesc *LocalBufferAlloc(Relation reln, BlockNumber blockNum,
bool *foundPtr);
extern void WriteLocalBuffer(Buffer buffer, bool release);
extern void DropRelFileNodeLocalBuffers(RelFileNode rnode,
BlockNumber firstDelBlock);
extern void AtEOXact_LocalBuffers(bool isCommit);
#endif /* BUFMGR_INTERNALS_H */