From d129c07499dbf0d5960115173515e3ce384c662a Mon Sep 17 00:00:00 2001 From: Peter Geoghegan Date: Sun, 9 Aug 2020 12:01:15 -0700 Subject: [PATCH] Correct nbtree page split lock coupling comment. There is no reason to distinguish between readers and writers here. --- src/backend/access/nbtree/nbtinsert.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c index e3a44bc09e0..d36f7557c87 100644 --- a/src/backend/access/nbtree/nbtinsert.c +++ b/src/backend/access/nbtree/nbtinsert.c @@ -1861,11 +1861,9 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, } /* - * We have to grab the right sibling (if any) and fix the prev pointer - * there. We are guaranteed that this is deadlock-free since no other - * writer will be holding a lock on that page and trying to move left, and - * all readers release locks on a page before trying to fetch its - * neighbors. + * We have to grab the original right sibling (if any) and update its prev + * link. We are guaranteed that this is deadlock-free, since we couple + * the locks in the standard order: left to right. */ if (!isrightmost) { -- 2.39.5