From 795da380a2b2a3867b03c22549ed093c4b4e4ddc Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Mon, 19 Jul 2021 18:17:54 +0000
Subject: [PATCH] Disable async rehash during load as it interferes with
 eviction

Former-commit-id: 54b4f39e9d634bf53b04cd94433b051b14323bc6
---
 src/db.cpp     | 2 +-
 src/server.cpp | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/db.cpp b/src/db.cpp
index 56556ff7f..adcf4456f 100644
--- a/src/db.cpp
+++ b/src/db.cpp
@@ -3020,7 +3020,7 @@ void redisDbPersistentData::removeAllCachedValues()
         trackChanges(false);
     }
 
-    if (m_pdict->pauserehash == 0) {
+    if (m_pdict->pauserehash == 0 && m_pdict->refcount == 1) {
         dict *dT = m_pdict;
         m_pdict = dictCreate(&dbDictType, this);
         dictExpand(m_pdict, dictSize(dT)/2, false); // Make room for about half so we don't excessively rehash
diff --git a/src/server.cpp b/src/server.cpp
index ed153d599..d32bec710 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -2124,7 +2124,7 @@ void databasesCron(bool fMainThread) {
                 ::dict *dict = g_pserver->db[rehash_db]->dictUnsafeKeyOnly();
                 /* Are we async rehashing? And if so is it time to re-calibrate? */
                 /* The recalibration limit is a prime number to ensure balancing across threads */
-                if (rehashes_per_ms > 0 && async_rehashes < 131 && !cserver.active_defrag_enabled && cserver.cthreads > 1) {
+                if (rehashes_per_ms > 0 && async_rehashes < 131 && !cserver.active_defrag_enabled && cserver.cthreads > 1 && dictSize(dict) > 2048 && dictIsRehashing(dict) && !g_pserver->loading) {
                     serverTL->rehashCtl = dictRehashAsyncStart(dict, rehashes_per_ms);
                     ++async_rehashes;
                 }