This should fix Issue 332: when there is a background process saving we still allow the hash tables to grow, but only when a critical treshold is reached. Formerly we prevented the resize at all triggering pathological O(N) behavior. Also there is a fix for the statistics in INFO about the number of keys expired

src/redis.c

@@ -1343,6 +1343,7 @@ void freeMemoryIfNeeded(void) {
                 }
                 keyobj = createStringObject(minkey,sdslen(minkey));
                 dbDelete(server.db+j,keyobj);
+                server.stat_expiredkeys++;
                 decrRefCount(keyobj);
             }
         }