From 98328ae2ecd0b7fd299d45e63ee25ec46aa92adc Mon Sep 17 00:00:00 2001
From: Martin Dimitrov <slice4e@users.noreply.github.com>
Date: Fri, 13 Feb 2026 23:45:54 -0700
Subject: [PATCH] Pause dict auto-resize during multi-field deletion (#14783)

The idea comes directly from ValKey:
https://github.com/valkey-io/valkey/pull/3144

Deleting many fields from a hash/zset/set stored as a dict can trigger
repeated shrink/rehash work during the loop.

---------

Co-authored-by: Binbin <binloveplay1314@qq.com>
Co-authored-by: debing.sun <debing.sun@redis.com>
---
 src/t_hash.c            | 9 +++++++++
 src/t_set.c             | 6 ++++++
 src/t_zset.c            | 6 ++++++
 tests/unit/type/set.tcl | 9 ++++++++-
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/t_hash.c b/src/t_hash.c
index d3720360b..830ecc52c 100644
--- a/src/t_hash.c
+++ b/src/t_hash.c
@@ -1,6 +1,9 @@
 /*
  * Copyright (c) 2009-Present, Redis Ltd.
  * All rights reserved.
+ * 
+ * Copyright (c) 2024-present, Valkey contributors.
+ * All rights reserved.
  *
  * Licensed under your choice of (a) the Redis Source Available License 2.0
  * (RSALv2); or (b) the Server Side Public License v1 (SSPLv1); or (c) the
@@ -2926,6 +2929,8 @@ void hdelCommand(client *c) {
      * field with expiration and removes it from global HFE DS. */
     int isHFE = hashTypeIsFieldsWithExpire(o);
 
+    if (o->encoding == OBJ_ENCODING_HT)
+        dictPauseAutoResize((dict*)o->ptr);
     for (j = 2; j < c->argc; j++) {
         if (hashTypeDelete(o,c->argv[j]->ptr)) {
             deleted++;
@@ -2939,6 +2944,10 @@ void hdelCommand(client *c) {
             }
         }
     }
+    if (!keyremoved && o->encoding == OBJ_ENCODING_HT) {
+        dictResumeAutoResize((dict*)o->ptr);
+        dictShrinkIfNeeded((dict*)o->ptr);
+    }
     if (server.memory_tracking_enabled && !keyremoved)
         updateSlotAllocSize(c->db, getKeySlot(c->argv[1]->ptr), o, oldsize, kvobjAllocSize(o));
     if (deleted) {
diff --git a/src/t_set.c b/src/t_set.c
index 6f2db737e..709b6ffec 100644
--- a/src/t_set.c
+++ b/src/t_set.c
@@ -657,6 +657,8 @@ void sremCommand(client *c) {
     if (server.memory_tracking_enabled)
         oldsize = kvobjAllocSize(set);
 
+    if (set->encoding == OBJ_ENCODING_HT)
+        dictPauseAutoResize((dict*)set->ptr);
     for (j = 2; j < c->argc; j++) {
         if (setTypeRemove(set,c->argv[j]->ptr)) {
             deleted++;
@@ -669,6 +671,10 @@ void sremCommand(client *c) {
             }
         }
     }
+    if (!keyremoved && set->encoding == OBJ_ENCODING_HT) {
+        dictResumeAutoResize((dict*)set->ptr);
+        dictShrinkIfNeeded((dict*)set->ptr);
+    }
     if (server.memory_tracking_enabled && !keyremoved)
         updateSlotAllocSize(c->db, getKeySlot(c->argv[1]->ptr), set, oldsize, kvobjAllocSize(set));
     if (deleted) {
diff --git a/src/t_zset.c b/src/t_zset.c
index da57c0998..bfc104f52 100644
--- a/src/t_zset.c
+++ b/src/t_zset.c
@@ -2118,6 +2118,8 @@ void zremCommand(client *c) {
     int64_t oldlen = (int64_t) zsetLength(zobj);
     if (server.memory_tracking_enabled)
         oldsize = kvobjAllocSize(zobj);
+    if (zobj->encoding == OBJ_ENCODING_SKIPLIST)
+        dictPauseAutoResize(((zset*)zobj->ptr)->dict);
     for (j = 2; j < c->argc; j++) {
         if (zsetDel(zobj, c->argv[j]->ptr)) deleted++;
         if (zsetLength(zobj) == 0) {
@@ -2129,6 +2131,10 @@ void zremCommand(client *c) {
             break;
         }
     }
+    if (!keyremoved && zobj->encoding == OBJ_ENCODING_SKIPLIST) {
+        dictResumeAutoResize(((zset*)zobj->ptr)->dict);
+        dictShrinkIfNeeded(((zset*)zobj->ptr)->dict);
+    }
 
     if (server.memory_tracking_enabled && !keyremoved)
         updateSlotAllocSize(c->db, getKeySlot(key->ptr), zobj, oldsize, kvobjAllocSize(zobj));
diff --git a/tests/unit/type/set.tcl b/tests/unit/type/set.tcl
index 054c9784e..ae315844d 100644
--- a/tests/unit/type/set.tcl
+++ b/tests/unit/type/set.tcl
@@ -1026,7 +1026,14 @@ foreach type {single multiple single_multiple} {
                 break
             }
         }
-        r srem $myset {*}$members
+        r deferred 1
+        foreach m $members {
+            r srem $myset $m
+        }
+        foreach m $members {
+            r read
+        }
+        r deferred 0
     }
 
     proc verify_rehashing_completed_key {myset table_size keys} {