0001-Bugfix.-Guard-total-number-of-hash-table-buckets.patch

From 9fb610126c607a6ced971d774127f2255ad0bbf8 Mon Sep 17 00:00:00 2001
From: "Andrey V. Lepikhov" <a.lepikhov@postgrespro.ru>
Date: Wed, 6 Dec 2023 10:52:05 +0700
Subject: [PATCH] Bugfix. Guard total number of hash table buckets.

It must be arranged with an max number, corresponding to maximum possible
allocated size of DSA memory.
---
 src/backend/executor/nodeHash.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/backend/executor/nodeHash.c b/src/backend/executor/nodeHash.c
index e72f0986c2..fdba7c85d3 100644
--- a/src/backend/executor/nodeHash.c
+++ b/src/backend/executor/nodeHash.c
@@ -1155,6 +1155,9 @@ ExecParallelHashIncreaseNumBatches(HashJoinTable hashtable)
 					double		dtuples;
 					double		dbuckets;
 					int			new_nbuckets;
+					const uint32 max_buckets =
+							pg_prevpower2_32((uint32)
+								(MaxAllocSize / sizeof(dsa_pointer_atomic)));
 
 					/*
 					 * We probably also need a smaller bucket array.  How many
@@ -1168,8 +1171,7 @@ ExecParallelHashIncreaseNumBatches(HashJoinTable hashtable)
 					 */
 					dtuples = (old_batch0->ntuples * 2.0) / new_nbatch;
 					dbuckets = ceil(dtuples / NTUP_PER_BUCKET);
-					dbuckets = Min(dbuckets,
-								   MaxAllocSize / sizeof(dsa_pointer_atomic));
+					dbuckets = Min(dbuckets, max_buckets);
 					new_nbuckets = (int) dbuckets;
 					new_nbuckets = Max(new_nbuckets, 1024);
 					new_nbuckets = pg_nextpower2_32(new_nbuckets);
-- 
2.43.0