On 10/24/07, Pavan Deolasee <[EMAIL PROTECTED]> wrote:
>
>
>
> I am looking at it. We must not call SetBufferCommitInfoNeedsSave unless
> we make any state changes to the page.
>
>
>
The attached patch should fix this. We mark the buffer dirty only if there
is any state change in the page header.
Thanks,
Pavan
--
Pavan Deolasee
EnterpriseDB http://www.enterprisedb.com
Index: src/backend/access/heap/pruneheap.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/access/heap/pruneheap.c,v
retrieving revision 1.2
diff -c -r1.2 pruneheap.c
*** src/backend/access/heap/pruneheap.c 21 Sep 2007 21:25:42 -0000 1.2
--- src/backend/access/heap/pruneheap.c 24 Oct 2007 09:32:21 -0000
***************
*** 146,162 ****
int nredirected = 0;
int ndead = 0;
int nunused = 0;
START_CRIT_SECTION();
/*
! * Mark the page as clear of prunable tuples. If we find a tuple which
! * may soon become prunable, we shall set the hint again. Also clear
! * the "page is full" flag, since there's no point in repeating the
! * prune/defrag process until something else happens to the page.
*/
PageClearPrunable(page);
! PageClearFull(page);
/* Scan the page */
maxoff = PageGetMaxOffsetNumber(page);
--- 146,173 ----
int nredirected = 0;
int ndead = 0;
int nunused = 0;
+ TransactionId save_prune_xid;
START_CRIT_SECTION();
/*
! * Save the current pd_prune_xid and mark the page as clear of prunable
! * tuples. If we find a tuple which may soon become prunable, we shall set
! * the hint again.
*/
+ save_prune_xid = ((PageHeader) page)->pd_prune_xid;
PageClearPrunable(page);
!
! /*
! * Also clear the "page is full" flag if it is set, since there's no point
! * in repeating the prune/defrag process until something else happens to the
! * page.
! */
! if (PageIsFull(page))
! {
! PageClearFull(page);
! SetBufferCommitInfoNeedsSave(buffer);
! }
/* Scan the page */
maxoff = PageGetMaxOffsetNumber(page);
***************
*** 209,218 ****
else
{
/*
! * If we didn't prune anything, we have nonetheless updated the
* pd_prune_xid field; treat this as a non-WAL-logged hint.
*/
! SetBufferCommitInfoNeedsSave(buffer);
}
END_CRIT_SECTION();
--- 220,230 ----
else
{
/*
! * If we didn't prune anything, but have updated the
* pd_prune_xid field; treat this as a non-WAL-logged hint.
*/
! if (((PageHeader) page)->pd_prune_xid != save_prune_xid)
! SetBufferCommitInfoNeedsSave(buffer);
}
END_CRIT_SECTION();
---------------------------(end of broadcast)---------------------------
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