All tests pass single thread

src/networking.cpp

@@ -1155,24 +1155,19 @@ static void freeClientArgv(client *c) {
  * resync with us as well. */
 void disconnectSlaves(void) {
     serverAssert(aeThreadOwnsLock());
-    std::vector<client*> vecfreeImmediate;
-    listNode *ln;
     listIter li;
+    listNode *ln;
+
     listRewind(server.slaves, &li);
     while ((ln = listNext(&li))) {
-        client *c = (client*)ln->value;
-        if (c->iel == serverTL - server.rgthreadvar)
-        {
-            vecfreeImmediate.push_back(c);
+        client *c = (client*)listNodeValue(ln);
+        if (FCorrectThread(c)) {
+            freeClient(c);
         }
-        else
-        {
+        else {
             freeClientAsync(c);
         }
     }
-
-    for (client *c : vecfreeImmediate)
-        freeClient(c);
 }
 
 /* Remove the specified client from global lists where the client could

src/object.c

@@ -986,6 +986,8 @@ struct redisMemOverhead *getMemoryOverheadData(void) {
         listRewind(server.slaves,&li);
         while((ln = listNext(&li))) {
             client *c = listNodeValue(ln);
+            if (c->flags & CLIENT_CLOSE_ASAP)
+                continue;
             mem += getClientOutputBufferMemoryUsage(c);
             mem += sdsAllocSize(c->querybuf);
             mem += sizeof(client);

src/replication.cpp

@@ -543,6 +543,9 @@ int masterTryPartialResynchronization(client *c) {
         buflen = snprintf(buf,sizeof(buf),"+CONTINUE\r\n");
     }
     if (write(c->fd,buf,buflen) != buflen) {
+        if (FCorrectThread(c))
+            freeClient(c);
+        else
             freeClientAsync(c);
         return C_OK;
     }
@@ -2011,6 +2014,9 @@ void replicationSetMaster(char *ip, int port) {
     server.masterhost = sdsnew(ip);
     server.masterport = port;
     if (server.master) {
+        if (FCorrectThread(server.master))
+            freeClient(server.master);
+        else
             freeClientAsync(server.master);
     }
     disconnectAllBlockedClients(); /* Clients blocked in master, now slave. */
@@ -2626,6 +2632,9 @@ void replicationCron(void) {
         (time(NULL)-server.master->lastinteraction) > server.repl_timeout)
     {
         serverLog(LL_WARNING,"MASTER timeout: no data nor PING received...");
+        if (FCorrectThread(server.master))
+            freeClient(server.master);
+        else
             freeClientAsync(server.master);
     }
 

tests/unit/lazyfree.tcl

@@ -19,6 +19,7 @@ start_server {tags {"lazyfree"}} {
     }
 
     test "FLUSHDB ASYNC can reclaim memory in background" {
+        after 500   # Sometimes Redis is busy with a prior operation
         set orig_mem [s used_memory]
         set args {}
         for {set i 0} {$i < 100000} {incr i} {