diff --git a/include/common/msgpack_util.hpp b/include/common/msgpack_util.hpp
index ae9eaab18547d52d235f841435c026c9c9337156..a1c280d388881853e4ca871d6dd4252bab89f246 100644
--- a/include/common/msgpack_util.hpp
+++ b/include/common/msgpack_util.hpp
@@ -65,14 +65,14 @@ public:
      * actually sent
      */
     struct msgpack_data {
-        uint32_t flush_t_;
+        uint64_t flush_t_;
         std::string hostname_;
         int pid_;
         std::string io_type_;
-        std::vector<uint32_t> start_t_{};
-        std::vector<uint32_t> end_t_{};
-        std::vector<uint32_t> req_size_{};
-        uint32_t total_bytes_{};
+        std::vector<uint64_t> start_t_{};
+        std::vector<uint64_t> end_t_{};
+        std::vector<uint64_t> req_size_{};
+        uint64_t total_bytes_{};
         int total_iops_{0};
 
         template <class T>
diff --git a/src/common/msgpack_util.cpp b/src/common/msgpack_util.cpp
index 1f18e1d9da28ebe1dc6f9400e59e40066a46ad64..687bacf503fbe30091b1f95a9e33aa9a8186e6e5 100644
--- a/src/common/msgpack_util.cpp
+++ b/src/common/msgpack_util.cpp
@@ -94,6 +94,8 @@ ClientMetrics::~ClientMetrics() {
     if(flush_thread_.joinable())
         flush_thread_.join();
     if(flush_type_ == client_metric_flush_type::socket) {
+        // flush before closing
+        flush_msgpack();
         zmq_flush_socket_->close();
         zmq_flush_context_->close();
     }