From d57883bf6443b679d22b6942b05af49dab188d22 Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Fri, 15 Oct 2021 16:22:42 +0000
Subject: [PATCH 1/5] Permit prefetch for FLASH scenarios in single thread mode

Former-commit-id: 6d0b90ed43cc9d1196903ddbc7d50cd40e439e42
---
 src/networking.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/networking.cpp b/src/networking.cpp
index d8b3e9a5d..1638328c0 100644
--- a/src/networking.cpp
+++ b/src/networking.cpp
@@ -2547,7 +2547,7 @@ void parseClientCommandBuffer(client *c) {
         }
 
         /* Prefetch outside the lock for better perf */
-        if (g_pserver->prefetch_enabled && cserver.cthreads > 1 && cqueriesStart < c->vecqueuedcmd.size() &&
+        if (g_pserver->prefetch_enabled && (cserver.cthreads > 1 || g_pserver->m_pstorageFactory) && cqueriesStart < c->vecqueuedcmd.size() &&
             (g_pserver->m_pstorageFactory || aeLockContested(cserver.cthreads/2) || cserver.cthreads == 1) && !GlobalLocksAcquired()) {
             auto &query = c->vecqueuedcmd.back();
             if (query.argc > 0 && query.argc == query.argcMax) {

From 43a62493f872874e965b3edbbfaba199c292d675 Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Wed, 20 Oct 2021 03:13:36 +0000
Subject: [PATCH 2/5] Additional change to ensure FLASH storage goes through
 the multithread path

Former-commit-id: 422ea0723f0b8718f28ef9c1cc4d5f56d374af46
---
 src/networking.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/networking.cpp b/src/networking.cpp
index 1638328c0..72b2ec59e 100644
--- a/src/networking.cpp
+++ b/src/networking.cpp
@@ -2694,7 +2694,7 @@ void readQueryFromClient(connection *conn) {
         return;
     }
 
-    if (cserver.cthreads > 1) {
+    if (cserver.cthreads > 1 || g_pserver->m_pstorageFactory) {
         parseClientCommandBuffer(c);
         serverTL->vecclientsProcess.push_back(c);
     } else {

From 7b3337d244bf718f0fb15b0db8a194a3ed9dd974 Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Thu, 21 Oct 2021 22:46:17 +0000
Subject: [PATCH 3/5] Ensure async rehash completes before we start a new time.
  Degrad to sync hash if necessary to ensure this

Former-commit-id: 0f830facc7c6bc6668af9bb2e10b6e13a13227aa
---
 src/server.cpp | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/server.cpp b/src/server.cpp
index ef1039cea..f257883e0 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -2112,12 +2112,11 @@ void databasesCron(bool fMainThread) {
         if (g_pserver->activerehashing) {
             for (j = 0; j < dbs_per_call; j++) {
                 if (serverTL->rehashCtl != nullptr) {
-                    if (dictRehashSomeAsync(serverTL->rehashCtl, 5)) {
+                    if (dictRehashSomeAsync(serverTL->rehashCtl, rehashes_per_ms)) {
                         break;
-                    } else {
-                        dictCompleteRehashAsync(serverTL->rehashCtl, true /*fFree*/);
-                        serverTL->rehashCtl = nullptr;
-                    }
+                    } 
+                    dictCompleteRehashAsync(serverTL->rehashCtl, true /*fFree*/);
+                    serverTL->rehashCtl = nullptr;
                 }
 
                 serverAssert(serverTL->rehashCtl == nullptr);

From 3f089054080d98e8a87d8bdbf2c5f4deba1595a1 Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Thu, 21 Oct 2021 23:45:46 +0000
Subject: [PATCH 4/5] Do not dereference a nullptr if there are too many files
 open

Former-commit-id: 4674eb29a261e8b046953398c94354fc3e550c2a
---
 src/server.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/server.cpp b/src/server.cpp
index f257883e0..1794f51e8 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -3793,8 +3793,6 @@ static void initServerThread(struct redisServerThreadVars *pvar, int fMain)
     pvar->in_eval = 0;
     pvar->in_exec = 0;
     pvar->el = aeCreateEventLoop(g_pserver->maxclients+CONFIG_FDSET_INCR);
-    aeSetBeforeSleepProc(pvar->el, beforeSleep, AE_SLEEP_THREADSAFE);
-    aeSetAfterSleepProc(pvar->el, afterSleep, AE_SLEEP_THREADSAFE);
     pvar->current_client = nullptr;
     pvar->fRetrySetAofEvent = false;
     if (pvar->el == NULL) {
@@ -3803,6 +3801,8 @@ static void initServerThread(struct redisServerThreadVars *pvar, int fMain)
             strerror(errno));
         exit(1);
     }
+    aeSetBeforeSleepProc(pvar->el, beforeSleep, AE_SLEEP_THREADSAFE);
+    aeSetAfterSleepProc(pvar->el, afterSleep, AE_SLEEP_THREADSAFE);
 
     fastlock_init(&pvar->lockPendingWrite, "lockPendingWrite");
 

From fbe9ff66804cc8d48e3919ab1e18bea9949b6327 Mon Sep 17 00:00:00 2001
From: malavan <malavan@eqalpha.com>
Date: Thu, 21 Oct 2021 23:50:50 +0000
Subject: [PATCH 5/5] null check for delete override

Former-commit-id: f5f2f5e200a5ff1b0306998624b758d5a4c10825
---
 src/new.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/new.cpp b/src/new.cpp
index 4775e207a..4e6b07dfd 100644
--- a/src/new.cpp
+++ b/src/new.cpp
@@ -27,14 +27,17 @@ void *operator new(std::size_t size, const std::nothrow_t &) noexcept
     return zmalloc(size, MALLOC_LOCAL);
 }
 
+//need to do null checks for delete since the compiler can optimize out null checks in zfree
 void operator delete(void * p) noexcept
 {
-    zfree(p);
+    if (p != nullptr)
+        zfree(p);
 }
 
 void operator delete(void *p, std::size_t) noexcept
 {
-    zfree(p);
+    if (p != nullptr)
+        zfree(p);
 }
 
 #endif