diff options
Diffstat (limited to 'src/backend/access/spgist/spgvacuum.c')
| -rw-r--r-- | src/backend/access/spgist/spgvacuum.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/src/backend/access/spgist/spgvacuum.c b/src/backend/access/spgist/spgvacuum.c index 4598ea8d67f..a09da84a2aa 100644 --- a/src/backend/access/spgist/spgvacuum.c +++ b/src/backend/access/spgist/spgvacuum.c @@ -307,7 +307,7 @@ vacuumLeafPage(spgBulkDeleteState *bds, Relation index, Buffer buffer) } /* - * Vacuum the root page when it is a leaf + * Vacuum a root page when it is also a leaf * * On the root, we just delete any dead leaf tuples; no fancy business */ @@ -321,6 +321,7 @@ vacuumLeafRoot(spgBulkDeleteState *bds, Relation index, Buffer buffer) OffsetNumber i, max = PageGetMaxOffsetNumber(page); + xlrec.blkno = BufferGetBlockNumber(buffer); xlrec.nDelete = 0; /* Scan page, identify tuples to delete, accumulate stats */ @@ -537,7 +538,7 @@ spgvacuumpage(spgBulkDeleteState *bds, BlockNumber blkno) } else if (SpGistPageIsLeaf(page)) { - if (blkno == SPGIST_HEAD_BLKNO) + if (SpGistBlockIsRoot(blkno)) { vacuumLeafRoot(bds, index, buffer); /* no need for vacuumRedirectAndPlaceholder */ @@ -560,7 +561,7 @@ spgvacuumpage(spgBulkDeleteState *bds, BlockNumber blkno) * put a new tuple. Otherwise, check for empty/deletable page, and * make sure FSM knows about it. */ - if (blkno != SPGIST_HEAD_BLKNO) + if (!SpGistBlockIsRoot(blkno)) { /* If page is now empty, mark it deleted */ if (PageIsEmpty(page) && !SpGistPageIsDeleted(page)) @@ -598,7 +599,7 @@ spgvacuumscan(spgBulkDeleteState *bds) /* Finish setting up spgBulkDeleteState */ initSpGistState(&bds->spgstate, index); bds->OldestXmin = GetOldestXmin(true, false); - bds->lastFilledBlock = SPGIST_HEAD_BLKNO; + bds->lastFilledBlock = SPGIST_LAST_FIXED_BLKNO; /* * Reset counts that will be incremented during the scan; needed in case @@ -619,7 +620,7 @@ spgvacuumscan(spgBulkDeleteState *bds) * delete some deletable tuples. See more extensive comments about * this in btvacuumscan(). */ - blkno = SPGIST_HEAD_BLKNO; + blkno = SPGIST_METAPAGE_BLKNO + 1; for (;;) { /* Get the current relation length */ @@ -648,6 +649,12 @@ spgvacuumscan(spgBulkDeleteState *bds) * XXX disabled because it's unsafe due to possible concurrent inserts. * We'd have to rescan the pages to make sure they're still empty, and it * doesn't seem worth it. Note that btree doesn't do this either. + * + * Another reason not to truncate is that it could invalidate the cached + * pages-with-freespace pointers in the metapage and other backends' + * relation caches, that is leave them pointing to nonexistent pages. + * Adding RelationGetNumberOfBlocks calls to protect the places that use + * those pointers would be unduly expensive. */ #ifdef NOT_USED if (num_pages > bds->lastFilledBlock + 1) |