diff --git a/dbms/src/Flash/FlashService.cpp b/dbms/src/Flash/FlashService.cpp
index 141239b10cb..03c38888a09 100644
--- a/dbms/src/Flash/FlashService.cpp
+++ b/dbms/src/Flash/FlashService.cpp
@@ -46,6 +46,15 @@ FlashService::FlashService(IServer & server_)
     batch_cop_pool = std::make_unique<ThreadPool>(batch_cop_pool_size, [] { setThreadName("batch-cop-pool"); });
 }
 
+// Use executeInThreadPool to submit job to thread pool which return grpc::Status.
+grpc::Status executeInThreadPool(const std::unique_ptr<ThreadPool> & pool, std::function<grpc::Status()> job)
+{
+    std::packaged_task<grpc::Status()> task(job);
+    std::future<grpc::Status> future = task.get_future();
+    pool->schedule([&task] { task(); });
+    return future.get();
+}
+
 grpc::Status FlashService::Coprocessor(
     grpc::ServerContext * grpc_context,
     const coprocessor::Request * request,
@@ -337,14 +346,6 @@ String getClientMetaVarWithDefault(const grpc::ServerContext * grpc_context, con
     return default_val;
 }
 
-grpc::Status FlashService::executeInThreadPool(const std::unique_ptr<ThreadPool> & pool, std::function<grpc::Status()> job)
-{
-    std::packaged_task<grpc::Status()> task(job);
-    std::future<grpc::Status> future = task.get_future();
-    pool->schedule([&task] { task(); });
-    return future.get();
-}
-
 std::tuple<ContextPtr, grpc::Status> FlashService::createDBContext(const grpc::ServerContext * grpc_context) const
 {
     try
diff --git a/dbms/src/Flash/FlashService.h b/dbms/src/Flash/FlashService.h
index 4c64404dd73..e09158e1ecd 100644
--- a/dbms/src/Flash/FlashService.h
+++ b/dbms/src/Flash/FlashService.h
@@ -57,10 +57,6 @@ class FlashService final : public tikvpb::Tikv::Service
 private:
     std::tuple<ContextPtr, ::grpc::Status> createDBContext(const grpc::ServerContext * grpc_context) const;
 
-    // Use executeInThreadPool to submit job to thread pool which return grpc::Status.
-    grpc::Status executeInThreadPool(const std::unique_ptr<ThreadPool> & pool, std::function<grpc::Status()>);
-
-private:
     IServer & server;
     const TiFlashSecurityConfig & security_config;
     Poco::Logger * log;