diff options
Diffstat (limited to 'src/backend/storage/page/bufpage.c')
| -rw-r--r-- | src/backend/storage/page/bufpage.c | 37 |
1 files changed, 29 insertions, 8 deletions
diff --git a/src/backend/storage/page/bufpage.c b/src/backend/storage/page/bufpage.c index 8299f550d6e..b246b0afeb8 100644 --- a/src/backend/storage/page/bufpage.c +++ b/src/backend/storage/page/bufpage.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/page/bufpage.c,v 1.71 2007/02/21 20:02:17 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/storage/page/bufpage.c,v 1.72 2007/03/02 00:48:44 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -39,6 +39,7 @@ PageInit(Page page, Size pageSize, Size specialSize) /* Make sure all fields of page are zero, as well as unused space */ MemSet(p, 0, pageSize); + /* p->pd_flags = 0; done by above MemSet */ p->pd_lower = SizeOfPageHeaderData; p->pd_upper = pageSize - specialSize; p->pd_special = pageSize - specialSize; @@ -73,6 +74,7 @@ PageHeaderIsValid(PageHeader page) /* Check normal case */ if (PageGetPageSize(page) == BLCKSZ && PageGetPageLayoutVersion(page) == PG_PAGE_LAYOUT_VERSION && + (page->pd_flags & ~PD_VALID_FLAG_BITS) == 0 && page->pd_lower >= SizeOfPageHeaderData && page->pd_lower <= page->pd_upper && page->pd_upper <= page->pd_special && @@ -165,14 +167,27 @@ PageAddItem(Page page, else { /* offsetNumber was not passed in, so find a free slot */ - /* look for "recyclable" (unused & deallocated) ItemId */ - for (offsetNumber = 1; offsetNumber < limit; offsetNumber++) + /* if no free slot, we'll put it at limit (1st open slot) */ + if (PageHasFreeLinePointers(phdr)) + { + /* look for "recyclable" (unused & deallocated) ItemId */ + for (offsetNumber = 1; offsetNumber < limit; offsetNumber++) + { + itemId = PageGetItemId(phdr, offsetNumber); + if (!ItemIdIsUsed(itemId) && ItemIdGetLength(itemId) == 0) + break; + } + if (offsetNumber >= limit) + { + /* the hint is wrong, so reset it */ + PageClearHasFreeLinePointers(phdr); + } + } + else { - itemId = PageGetItemId(phdr, offsetNumber); - if (!ItemIdIsUsed(itemId) && ItemIdGetLength(itemId) == 0) - break; + /* don't bother searching if hint says there's no free slot */ + offsetNumber = limit; } - /* if no free slot, we'll put it at limit (1st open slot) */ } if (offsetNumber > limit) @@ -413,13 +428,19 @@ PageRepairFragmentation(Page page, OffsetNumber *unused) pfree(itemidbase); } + /* Set hint bit for PageAddItem */ + if (nused < nline) + PageSetHasFreeLinePointers(page); + else + PageClearHasFreeLinePointers(page); + return (nline - nused); } /* * PageGetFreeSpace * Returns the size of the free (allocatable) space on a page, - * deducted by the space needed for a new line pointer. + * reduced by the space needed for a new line pointer. */ Size PageGetFreeSpace(Page page) |