diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2007-09-20 17:56:33 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2007-09-20 17:56:33 +0000 |
| commit | 282d2a03dd30804b01f8042f640d638c2ee76604 (patch) | |
| tree | 004f08ce31f1bfb03ab55571ad7867babe5b3d7f /src/backend/access/heap/hio.c | |
| parent | bbf4fdc2538097bb3103806e1419ceef1f289203 (diff) | |
HOT updates. When we update a tuple without changing any of its indexed
columns, and the new version can be stored on the same heap page, we no longer
generate extra index entries for the new version. Instead, index searches
follow the HOT-chain links to ensure they find the correct tuple version.
In addition, this patch introduces the ability to "prune" dead tuples on a
per-page basis, without having to do a complete VACUUM pass to recover space.
VACUUM is still needed to clean up dead index entries, however.
Pavan Deolasee, with help from a bunch of other people.
Diffstat (limited to 'src/backend/access/heap/hio.c')
| -rw-r--r-- | src/backend/access/heap/hio.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/src/backend/access/heap/hio.c b/src/backend/access/heap/hio.c index 6dbdf13fbe0..cd13d8f87c9 100644 --- a/src/backend/access/heap/hio.c +++ b/src/backend/access/heap/hio.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/heap/hio.c,v 1.66 2007/09/12 22:10:26 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/heap/hio.c,v 1.67 2007/09/20 17:56:30 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -41,7 +41,7 @@ RelationPutHeapTuple(Relation relation, pageHeader = BufferGetPage(buffer); offnum = PageAddItem(pageHeader, (Item) tuple->t_data, - tuple->t_len, InvalidOffsetNumber, false); + tuple->t_len, InvalidOffsetNumber, false, true); if (offnum == InvalidOffsetNumber) elog(PANIC, "failed to add tuple to page"); @@ -218,7 +218,7 @@ RelationGetBufferForTuple(Relation relation, Size len, * we're done. */ pageHeader = (Page) BufferGetPage(buffer); - pageFreeSpace = PageGetFreeSpace(pageHeader); + pageFreeSpace = PageGetHeapFreeSpace(pageHeader); if (len + saveFreeSpace <= pageFreeSpace) { /* use this page as future insert target, too */ @@ -311,7 +311,7 @@ RelationGetBufferForTuple(Relation relation, Size len, PageInit(pageHeader, BufferGetPageSize(buffer), 0); - if (len > PageGetFreeSpace(pageHeader)) + if (len > PageGetHeapFreeSpace(pageHeader)) { /* We should not get here given the test at the top */ elog(PANIC, "tuple is too big: size %lu", (unsigned long) len); |