diff --git a/cpp/src/db/scheduler/task/SearchTask.cpp b/cpp/src/db/scheduler/task/SearchTask.cpp
index e696faaed044b388da57096500c043133b158287..79baeeafe9f7d2d23e04a55c0cd2d9b4454ce97c 100644
--- a/cpp/src/db/scheduler/task/SearchTask.cpp
+++ b/cpp/src/db/scheduler/task/SearchTask.cpp
@@ -22,7 +22,7 @@ static constexpr size_t PARALLEL_REDUCE_BATCH = 1000;
 bool NeedParallelReduce(uint64_t nq, uint64_t topk) {
     server::ServerConfig &config = server::ServerConfig::GetInstance();
     server::ConfigNode& db_config = config.GetConfig(server::CONFIG_DB);
-    bool need_parallel = db_config.GetBoolValue(server::CONFIG_DB_PARALLEL_REDUCE, true);
+    bool need_parallel = db_config.GetBoolValue(server::CONFIG_DB_PARALLEL_REDUCE, false);
     if(!need_parallel) {
         return false;
     }