From 56c0663e231c46fb16ab31b604e9d33265aeb6b9 Mon Sep 17 00:00:00 2001 From: Amit Kapila Date: Fri, 11 Sep 2020 16:15:03 +0530 Subject: [PATCH v2] Update parallel BTree scan state when the scan keys can't be satisfied. For parallel btree scan to work for array of scan keys, it should reach BTPARALLEL_DONE state once for every distinct combination of array keys. This is required to ensure that the parallel workers don't try to seize blocks at the same time for different scan keys. We missed to update this state when we discovered that the scan keys can't be satisfied. Author: James Hunter Reviewed-by: Amit Kapila Tested-by: Justin Pryzby Backpatch-through: 10, where it was introduced Discussion: https://postgr.es/m/4248CABC-25E3-4809-B4D0-128E1BAABC3C@amazon.com --- src/backend/access/nbtree/nbtsearch.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index 1e628a33d7..8f6575fdf1 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -880,7 +880,11 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) * never be satisfied (eg, x == 1 AND x > 2). */ if (!so->qual_ok) + { + /* Notify any other workers that we're done with this scan key. */ + _bt_parallel_done(scan); return false; + } /* * For parallel scans, get the starting page from shared state. If the -- 2.28.0.windows.1