From ca559819f7dcd97ba9ef667bf38360a9527d62f6 Mon Sep 17 00:00:00 2001
From: menwen <menwenjun@gmail.com>
Date: Thu, 5 Aug 2021 16:09:24 +0800
Subject: [PATCH] Add latency monitor sample when key is deleted via lazy
 expire (#9317)

Fix that there is no sample latency after the key expires via expireIfNeeded().
Some refactoring for shared code.
---
 src/db.c     | 28 ++++++++++++++++++----------
 src/expire.c | 15 +--------------
 src/server.h |  1 +
 3 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/src/db.c b/src/db.c
index 3926bd33f..2e3009d7a 100644
--- a/src/db.c
+++ b/src/db.c
@@ -30,6 +30,7 @@
 #include "server.h"
 #include "cluster.h"
 #include "atomicvar.h"
+#include "latency.h"
 
 #include <signal.h>
 #include <ctype.h>
@@ -1437,6 +1438,22 @@ long long getExpire(redisDb *db, robj *key) {
     return dictGetSignedIntegerVal(de);
 }
 
+/* Delete the specified expired key and propagate expire. */
+void deleteExpiredKeyAndPropagate(redisDb *db, robj *keyobj) {
+    mstime_t expire_latency;
+    latencyStartMonitor(expire_latency);
+    if (server.lazyfree_lazy_expire)
+        dbAsyncDelete(db,keyobj);
+    else
+        dbSyncDelete(db,keyobj);
+    latencyEndMonitor(expire_latency);
+    latencyAddSampleIfNeeded("expire-del",expire_latency);
+    notifyKeyspaceEvent(NOTIFY_EXPIRED,"expired",keyobj,db->id);
+    signalModifiedKey(NULL, db, keyobj);
+    propagateExpire(db,keyobj,server.lazyfree_lazy_expire);
+    server.stat_expiredkeys++;
+}
+
 /* Propagate expires into slaves and the AOF file.
  * When a key expires in the master, a DEL operation for this key is sent
  * to all the slaves and the AOF file if enabled.
@@ -1541,16 +1558,7 @@ int expireIfNeeded(redisDb *db, robj *key) {
     if (checkClientPauseTimeoutAndReturnIfPaused()) return 1;
 
     /* Delete the key */
-    if (server.lazyfree_lazy_expire) {
-        dbAsyncDelete(db,key);
-    } else {
-        dbSyncDelete(db,key);
-    }
-    server.stat_expiredkeys++;
-    propagateExpire(db,key,server.lazyfree_lazy_expire);
-    notifyKeyspaceEvent(NOTIFY_EXPIRED,
-        "expired",key,db->id);
-    signalModifiedKey(NULL,db,key);
+    deleteExpiredKeyAndPropagate(db,key);
     return 1;
 }
 
diff --git a/src/expire.c b/src/expire.c
index 858c13549..798651255 100644
--- a/src/expire.c
+++ b/src/expire.c
@@ -53,24 +53,11 @@
  * to the function to avoid too many gettimeofday() syscalls. */
 int activeExpireCycleTryExpire(redisDb *db, dictEntry *de, long long now) {
     long long t = dictGetSignedIntegerVal(de);
-    mstime_t expire_latency;
     if (now > t) {
         sds key = dictGetKey(de);
         robj *keyobj = createStringObject(key,sdslen(key));
-
-        propagateExpire(db,keyobj,server.lazyfree_lazy_expire);
-        latencyStartMonitor(expire_latency);
-        if (server.lazyfree_lazy_expire)
-            dbAsyncDelete(db,keyobj);
-        else
-            dbSyncDelete(db,keyobj);
-        latencyEndMonitor(expire_latency);
-        latencyAddSampleIfNeeded("expire-del",expire_latency);
-        notifyKeyspaceEvent(NOTIFY_EXPIRED,
-            "expired",keyobj,db->id);
-        signalModifiedKey(NULL, db, keyobj);
+        deleteExpiredKeyAndPropagate(db,keyobj);
         decrRefCount(keyobj);
-        server.stat_expiredkeys++;
         return 1;
     } else {
         return 0;
diff --git a/src/server.h b/src/server.h
index 5516dab29..dbef3c2de 100644
--- a/src/server.h
+++ b/src/server.h
@@ -2377,6 +2377,7 @@ void initConfigValues();
 
 /* db.c -- Keyspace access API */
 int removeExpire(redisDb *db, robj *key);
+void deleteExpiredKeyAndPropagate(redisDb *db, robj *keyobj);
 void propagateExpire(redisDb *db, robj *key, int lazy);
 int keyIsExpired(redisDb *db, robj *key);
 int expireIfNeeded(redisDb *db, robj *key);