Disable multithreaded KEYS due to bugs

Author: JohnSully

src/db.cpp

@@ -643,7 +643,9 @@ void keysCommand(client *c) {
     unsigned long numkeys = 0;
     void *replylen = addReplyDeferredLen(c);
 
+#ifdef MULTITHREADED_KEYS
     aeReleaseLock();
+#endif
 
     di = dictGetSafeIterator(c->db->pdict);
     allkeys = (pattern[0] == '*' && pattern[1] == '\0');
@@ -663,11 +665,13 @@ void keysCommand(client *c) {
     dictReleaseIterator(di);
     setDeferredArrayLen(c,replylen,numkeys);
 
+#ifdef MULTITHREADED_KEYS
     fastlock_unlock(&c->db->lock);  // we must release the DB lock before acquiring the AE lock to prevent deadlocks
     AeLocker lock;
     lock.arm(c);
     fastlock_lock(&c->db->lock);    // we still need the DB lock
     lock.release();
+#endif
 }
 
 /* This callback is used by scanGenericCommand in order to collect elements