diff --git a/deps/oblib/src/rpc/obrpc/ob_poc_rpc_proxy.cpp b/deps/oblib/src/rpc/obrpc/ob_poc_rpc_proxy.cpp
index dc52110f8..d01cb6ce0 100644
--- a/deps/oblib/src/rpc/obrpc/ob_poc_rpc_proxy.cpp
+++ b/deps/oblib/src/rpc/obrpc/ob_poc_rpc_proxy.cpp
@@ -33,9 +33,11 @@ common::ObCompressorType get_proxy_compressor_type(ObRpcProxy& proxy) {
 int ObSyncRespCallback::handle_resp(int io_err, const char* buf, int64_t sz)
 {
   if (PNIO_OK != io_err) {
-    if (PNIO_TIMEOUT == io_err) {
+    if (PNIO_TIMEOUT == io_err || PNIO_DISCONNECT == io_err || PNIO_PKT_TERMINATE == io_err) {
+      // these pnio error means not sure rpc was successfully sent
       send_ret_ = OB_TIMEOUT;
     } else {
+      // OB_RPC_SEND_ERROR means the rpc must not have been sent out
       send_ret_ = OB_RPC_SEND_ERROR;
       RPC_LOG_RET(WARN, send_ret_, "pnio error", KP(buf), K(sz), K(io_err));
     }
diff --git a/deps/oblib/src/rpc/pnio/interface/group.h b/deps/oblib/src/rpc/pnio/interface/group.h
index 1323f56f7..20f76fe84 100644
--- a/deps/oblib/src/rpc/pnio/interface/group.h
+++ b/deps/oblib/src/rpc/pnio/interface/group.h
@@ -110,6 +110,7 @@ void pn_print_diag_info(pn_comm_t* pn_comm);
 #define PNIO_DISCONNECT_NOT_SENT_OUT    (-55)
 #define PNIO_LISTEN_ERROR               (-56)
 #define PNIO_PKT_TERMINATE              (-57)
+#define PNIO_PKT_TERMINATE_NOT_SENT_OUT (-58)
 
 enum {
   PN_NORMAL_PKT = 0,
diff --git a/deps/oblib/src/rpc/pnio/io/write_queue.c b/deps/oblib/src/rpc/pnio/io/write_queue.c
index 5158860ef..492a75fbf 100644
--- a/deps/oblib/src/rpc/pnio/io/write_queue.c
+++ b/deps/oblib/src/rpc/pnio/io/write_queue.c
@@ -87,8 +87,8 @@ inline void wq_push(write_queue_t* wq, dlink_t* l) {
 
 inline int wq_delete(write_queue_t* wq, dlink_t* l) {
   int err = PNIO_OK;
-  if (dqueue_top(&wq->queue) == l) {
-    // not to delete the first req of write_queue
+  if (dqueue_top(&wq->queue) == l && wq->pos > 0) {
+    // req has been sending, it cannot be deleted
     err = PNIO_ERROR;
   } else if (l == l->prev) {
     // req hasn't been inserted into flush_list
diff --git a/deps/oblib/src/rpc/pnio/nio/pktc_resp.h b/deps/oblib/src/rpc/pnio/nio/pktc_resp.h
index 40bd69819..52af7394c 100644
--- a/deps/oblib/src/rpc/pnio/nio/pktc_resp.h
+++ b/deps/oblib/src/rpc/pnio/nio/pktc_resp.h
@@ -26,6 +26,8 @@ static void pktc_do_cb_exception(pktc_t* io, pktc_cb_t* cb) {
         cb->errcode = PNIO_DISCONNECT_NOT_SENT_OUT;
       } else if (cb->errcode == PNIO_TIMEOUT) {
         cb->errcode = PNIO_TIMEOUT_NOT_SENT_OUT;
+      } else if (cb->errcode == PNIO_PKT_TERMINATE){
+        cb->errcode = PNIO_PKT_TERMINATE_NOT_SENT_OUT;
       }
       pktc_flush_cb(io, req);
     }
diff --git a/deps/oblib/src/rpc/pnio/nio/pktc_sk_factory.h b/deps/oblib/src/rpc/pnio/nio/pktc_sk_factory.h
index ea328d3bf..fcf5b5ff7 100644
--- a/deps/oblib/src/rpc/pnio/nio/pktc_sk_factory.h
+++ b/deps/oblib/src/rpc/pnio/nio/pktc_sk_factory.h
@@ -84,8 +84,8 @@ static void pktc_sk_delete(pktc_sf_t* sf, pktc_sk_t* s) {
   pktc_t* io = structof(sf, pktc_t, sf);
   rk_info("sk_destroy: s=%p io=%p", s, io);
   pktc_sk_destroy(sf, s);
-  pktc_write_queue_on_sk_destroy(io, s);
   pktc_resp_cb_on_sk_destroy(io, s);
+  pktc_write_queue_on_sk_destroy(io, s);
   ib_destroy(&s->ib);
   dlink_delete(&s->rl_ready_link);
   pktc_sk_free(s);