From 2ffa295f4f0d5ea308ba298a1f6bf700c3f7e735 Mon Sep 17 00:00:00 2001 From: Peter Geoghegan Date: Thu, 18 Jul 2019 17:09:11 -0700 Subject: [PATCH] Set minimum amcheck Bloom filter size. --- contrib/amcheck/verify_nbtree.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index 9126c18d0e..c497d63bf9 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -377,11 +377,20 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace, if (state->heapallindexed) { + int64 total_pages; int64 total_elems; uint64 seed; - /* Size Bloom filter based on estimated number of tuples in index */ - total_elems = (int64) state->rel->rd_rel->reltuples; + /* + * Size Bloom filter based on estimated number of tuples in index, + * while conservatively assuming that each block must contain at least + * 50 non-pivot tuples. (Non-leaf pages cannot contain non-pivot + * tuples, but it shouldn't matter; leaf pages are almost never less + * than 98% of the total unless the index is very small.) + */ + total_pages = (int64) RelationGetNumberOfBlocks(rel); + total_elems = Max(total_pages * 50, + (int64) state->rel->rd_rel->reltuples); /* Random seed relies on backend srandom() call to avoid repetition */ seed = random(); /* Create Bloom filter to fingerprint index */ @@ -425,8 +434,6 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace, } else { - int64 total_pages; - /* * Extra readonly downlink check. * @@ -437,7 +444,6 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace, * splits and page deletions, though. This is taken care of in * bt_downlink_missing_check(). */ - total_pages = (int64) state->rel->rd_rel->relpages; state->downlinkfilter = bloom_create(total_pages, work_mem, seed); } } -- 2.17.1