diff --git a/core/src/db/DBImpl.cpp b/core/src/db/DBImpl.cpp
index ceac415eda..a1a305380b 100644
--- a/core/src/db/DBImpl.cpp
+++ b/core/src/db/DBImpl.cpp
@@ -68,7 +68,7 @@ TraverseFiles(const meta::DatePartionedTableFilesSchema& date_files, meta::Table
 }  // namespace
 
 DBImpl::DBImpl(const DBOptions& options)
-    : options_(options), shutting_down_(true), compact_thread_pool_(1, 1), index_thread_pool_(1, 1) {
+    : options_(options), initialized_(false), compact_thread_pool_(1, 1), index_thread_pool_(1, 1) {
     meta_ptr_ = MetaFactory::Build(options.meta_, options.mode_);
     mem_mgr_ = MemManagerFactory::Build(meta_ptr_, options_);
     Start();
@@ -83,12 +83,12 @@ DBImpl::~DBImpl() {
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 Status
 DBImpl::Start() {
-    if (!shutting_down_.load(std::memory_order_acquire)) {
+    if (initialized_.load(std::memory_order_acquire)) {
         return Status::OK();
     }
 
     // ENGINE_LOG_TRACE << "DB service start";
-    shutting_down_.store(false, std::memory_order_release);
+    initialized_.store(true, std::memory_order_release);
 
     // for distribute version, some nodes are read only
     if (options_.mode_ != DBOptions::MODE::CLUSTER_READONLY) {
@@ -101,11 +101,10 @@ DBImpl::Start() {
 
 Status
 DBImpl::Stop() {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return Status::OK();
     }
-
-    shutting_down_.store(true, std::memory_order_release);
+    initialized_.store(false, std::memory_order_release);
 
     // makesure all memory data serialized
     std::set<std::string> sync_table_ids;
@@ -129,7 +128,7 @@ DBImpl::DropAll() {
 
 Status
 DBImpl::CreateTable(meta::TableSchema& table_schema) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -140,7 +139,7 @@ DBImpl::CreateTable(meta::TableSchema& table_schema) {
 
 Status
 DBImpl::DropTable(const std::string& table_id, const meta::DatesT& dates) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -149,7 +148,7 @@ DBImpl::DropTable(const std::string& table_id, const meta::DatesT& dates) {
 
 Status
 DBImpl::DescribeTable(meta::TableSchema& table_schema) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -160,7 +159,7 @@ DBImpl::DescribeTable(meta::TableSchema& table_schema) {
 
 Status
 DBImpl::HasTable(const std::string& table_id, bool& has_or_not) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -169,7 +168,7 @@ DBImpl::HasTable(const std::string& table_id, bool& has_or_not) {
 
 Status
 DBImpl::AllTables(std::vector<meta::TableSchema>& table_schema_array) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -189,7 +188,7 @@ DBImpl::AllTables(std::vector<meta::TableSchema>& table_schema_array) {
 
 Status
 DBImpl::PreloadTable(const std::string& table_id) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -248,7 +247,7 @@ DBImpl::PreloadTable(const std::string& table_id) {
 
 Status
 DBImpl::UpdateTableFlag(const std::string& table_id, int64_t flag) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -257,7 +256,7 @@ DBImpl::UpdateTableFlag(const std::string& table_id, int64_t flag) {
 
 Status
 DBImpl::GetTableRowCount(const std::string& table_id, uint64_t& row_count) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -267,7 +266,7 @@ DBImpl::GetTableRowCount(const std::string& table_id, uint64_t& row_count) {
 Status
 DBImpl::CreatePartition(const std::string& table_id, const std::string& partition_name,
                         const std::string& partition_tag) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -276,7 +275,7 @@ DBImpl::CreatePartition(const std::string& table_id, const std::string& partitio
 
 Status
 DBImpl::DropPartition(const std::string& partition_name) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -294,7 +293,7 @@ DBImpl::DropPartition(const std::string& partition_name) {
 
 Status
 DBImpl::DropPartitionByTag(const std::string& table_id, const std::string& partition_tag) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -310,7 +309,7 @@ DBImpl::DropPartitionByTag(const std::string& table_id, const std::string& parti
 
 Status
 DBImpl::ShowPartitions(const std::string& table_id, std::vector<meta::TableSchema>& partition_schema_array) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -321,7 +320,7 @@ Status
 DBImpl::InsertVectors(const std::string& table_id, const std::string& partition_tag, uint64_t n, const float* vectors,
                       IDNumbers& vector_ids) {
     //    ENGINE_LOG_DEBUG << "Insert " << n << " vectors to cache";
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -346,7 +345,7 @@ DBImpl::InsertVectors(const std::string& table_id, const std::string& partition_
 
 Status
 DBImpl::CreateIndex(const std::string& table_id, const TableIndex& index) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -389,7 +388,7 @@ DBImpl::CreateIndex(const std::string& table_id, const TableIndex& index) {
 
 Status
 DBImpl::DescribeIndex(const std::string& table_id, TableIndex& index) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -398,7 +397,7 @@ DBImpl::DescribeIndex(const std::string& table_id, TableIndex& index) {
 
 Status
 DBImpl::DropIndex(const std::string& table_id) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -410,7 +409,7 @@ Status
 DBImpl::Query(const std::shared_ptr<server::Context>& context, const std::string& table_id,
               const std::vector<std::string>& partition_tags, uint64_t k, uint64_t nq, uint64_t nprobe,
               const float* vectors, ResultIds& result_ids, ResultDistances& result_distances) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -427,7 +426,7 @@ DBImpl::Query(const std::shared_ptr<server::Context>& context, const std::string
               ResultDistances& result_distances) {
     auto query_ctx = context->Child("Query");
 
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -476,7 +475,7 @@ DBImpl::QueryByFileID(const std::shared_ptr<server::Context>& context, const std
                       ResultDistances& result_distances) {
     auto query_ctx = context->Child("Query by file id");
 
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -512,7 +511,7 @@ DBImpl::QueryByFileID(const std::shared_ptr<server::Context>& context, const std
 
 Status
 DBImpl::Size(uint64_t& result) {
-    if (shutting_down_.load(std::memory_order_acquire)) {
+    if (!initialized_.load(std::memory_order_acquire)) {
         return SHUTDOWN_ERROR;
     }
 
@@ -566,7 +565,7 @@ DBImpl::BackgroundTimerTask() {
     Status status;
     server::SystemInfo::GetInstance().Init();
     while (true) {
-        if (shutting_down_.load(std::memory_order_acquire)) {
+        if (!initialized_.load(std::memory_order_acquire)) {
             WaitMergeFileFinish();
             WaitBuildIndexFinish();
 
@@ -802,7 +801,7 @@ DBImpl::BackgroundMergeFiles(const std::string& table_id) {
         MergeFiles(table_id, kv.first, kv.second);
         status = ongoing_files_checker_.UnmarkOngoingFiles(files);
 
-        if (shutting_down_.load(std::memory_order_acquire)) {
+        if (!initialized_.load(std::memory_order_acquire)) {
             ENGINE_LOG_DEBUG << "Server will shutdown, skip merge action for table: " << table_id;
             break;
         }
@@ -822,7 +821,7 @@ DBImpl::BackgroundCompaction(std::set<std::string> table_ids) {
             ENGINE_LOG_ERROR << "Merge files for table " << table_id << " failed: " << status.ToString();
         }
 
-        if (shutting_down_.load(std::memory_order_acquire)) {
+        if (!initialized_.load(std::memory_order_acquire)) {
             ENGINE_LOG_DEBUG << "Server will shutdown, skip merge action";
             break;
         }
diff --git a/core/src/db/DBImpl.h b/core/src/db/DBImpl.h
index c8b4fe4f73..3c9161f4d9 100644
--- a/core/src/db/DBImpl.h
+++ b/core/src/db/DBImpl.h
@@ -187,7 +187,7 @@ class DBImpl : public DB {
  private:
     const DBOptions options_;
 
-    std::atomic<bool> shutting_down_;
+    std::atomic<bool> initialized_;
 
     std::thread bg_timer_thread_;