diff --git a/src/common/backend/libpq/be-secure.cpp b/src/common/backend/libpq/be-secure.cpp
index 058d96a37..cab37b5d5 100644
--- a/src/common/backend/libpq/be-secure.cpp
+++ b/src/common/backend/libpq/be-secure.cpp
@@ -448,7 +448,7 @@ readloop:
 ssize_t secure_read(Port *port, void *ptr, size_t len)
 {
     ssize_t n = 0;
-    if (u_sess->attr.attr_common.light_comm == TRUE) {
+    if (g_instance.attr.attr_common.light_comm == TRUE) {
         n = light_secure_read(port, ptr, len);
     } else {
         n = old_secure_read(port, ptr, len);
@@ -696,7 +696,7 @@ retry:
 ssize_t secure_write(Port *port, void *ptr, size_t len)
 {
     ssize_t n = 0;
-    if (u_sess->attr.attr_common.light_comm == TRUE) {
+    if (g_instance.attr.attr_common.light_comm == TRUE) {
         n = light_secure_write(port, ptr, len);
     } else {
         n = old_secure_write(port, ptr, len);
diff --git a/src/common/backend/libpq/pqcomm.cpp b/src/common/backend/libpq/pqcomm.cpp
index 757486aea..dff215a44 100644
--- a/src/common/backend/libpq/pqcomm.cpp
+++ b/src/common/backend/libpq/pqcomm.cpp
@@ -464,7 +464,7 @@ void pq_init(void)
      * should always use COMMERROR on failure during communication
      */
 #ifndef WIN32
-    if (u_sess->attr.attr_common.light_comm == TRUE &&
+    if (g_instance.attr.attr_common.light_comm == TRUE &&
         u_sess->proc_cxt.MyProcPort->sock != PGINVALID_SOCKET && !pg_set_noblock(u_sess->proc_cxt.MyProcPort->sock)){
         ereport(COMMERROR, (errmsg("could not set socket to nonblocking mode: %m")));
     }
@@ -1172,7 +1172,7 @@ void TouchSocketFile(void)
  */
 void pq_set_nonblocking(bool nonblocking)
 {
-    if (u_sess->attr.attr_common.light_comm == FALSE) {
+    if (g_instance.attr.attr_common.light_comm == FALSE) {
         if (u_sess->proc_cxt.MyProcPort->noblock == nonblocking) {
             return;
         }
diff --git a/src/common/backend/utils/misc/guc.cpp b/src/common/backend/utils/misc/guc.cpp
index c3c376e70..21554bd15 100755
--- a/src/common/backend/utils/misc/guc.cpp
+++ b/src/common/backend/utils/misc/guc.cpp
@@ -1979,13 +1979,13 @@ static void InitConfigureNamesBool()
             NULL
         },
         {{"light_comm",
-            PGC_BACKEND,
+            PGC_POSTMASTER,
             NODE_ALL,
             CLIENT_CONN,
             gettext_noop("Enable to use light connection"),
             NULL,
             },
-            &u_sess->attr.attr_common.light_comm,
+            &g_instance.attr.attr_common.light_comm,
             false,
             NULL,
             NULL,
diff --git a/src/gausskernel/optimizer/commands/async.cpp b/src/gausskernel/optimizer/commands/async.cpp
index b34fb057f..28c631c31 100644
--- a/src/gausskernel/optimizer/commands/async.cpp
+++ b/src/gausskernel/optimizer/commands/async.cpp
@@ -1498,7 +1498,7 @@ void HandleNotifyInterrupt(void)
     notifyInterruptPending = true;
 
     /* make sure the event is processed in due course */
-    if (u_sess->attr.attr_common.light_comm== TRUE && t_thrd.proc) {
+    if (g_instance.attr.attr_common.light_comm== TRUE && t_thrd.proc) {
         SetLatch(&t_thrd.proc->procLatch);
     }
 }
diff --git a/src/gausskernel/process/tcop/postgres.cpp b/src/gausskernel/process/tcop/postgres.cpp
index 8ce3c992c..e15ef8997 100755
--- a/src/gausskernel/process/tcop/postgres.cpp
+++ b/src/gausskernel/process/tcop/postgres.cpp
@@ -486,7 +486,7 @@ static int InteractiveBackend(StringInfo inBuf)
 static int interactive_getc(void)
 {
     int c;
-    if (u_sess->attr.attr_common.light_comm == FALSE) {
+    if (g_instance.attr.attr_common.light_comm == FALSE) {
         prepare_for_client_read();
         c = getc(stdin);
         client_read_ended();
@@ -6064,7 +6064,7 @@ void die(SIGNAL_ARGS)
     if (t_thrd.proc)
         SetLatch(&t_thrd.proc->procLatch);
 
-    if (u_sess->attr.attr_common.light_comm == TRUE &&
+    if (g_instance.attr.attr_common.light_comm == TRUE &&
         t_thrd.postgres_cxt.DoingCommandRead &&
         t_thrd.postgres_cxt.whereToSendOutput != DestRemote) {
         ProcessInterrupts();
diff --git a/src/gausskernel/storage/ipc/sinval.cpp b/src/gausskernel/storage/ipc/sinval.cpp
index b501e7b53..5954ffc5e 100644
--- a/src/gausskernel/storage/ipc/sinval.cpp
+++ b/src/gausskernel/storage/ipc/sinval.cpp
@@ -225,7 +225,7 @@ void HandleCatchupInterrupt(void)
      * you do here.
      */
     catchupInterruptPending = true;
-    if (u_sess->attr.attr_common.light_comm == TRUE && t_thrd.proc) {
+    if (g_instance.attr.attr_common.light_comm == TRUE && t_thrd.proc) {
         SetLatch(&t_thrd.proc->procLatch);
     }
 }
diff --git a/src/include/knl/knl_guc/knl_session_attr_common.h b/src/include/knl/knl_guc/knl_session_attr_common.h
index 5902798a3..47da2d5ab 100644
--- a/src/include/knl/knl_guc/knl_session_attr_common.h
+++ b/src/include/knl/knl_guc/knl_session_attr_common.h
@@ -240,7 +240,6 @@ typedef struct knl_session_attr_common {
     int threadpool_reset_percent_list[2];
     bool enable_indexscan_optimization;
     char* delimiter_name;
-    bool light_comm;
     bool test_user_host;
 } knl_session_attr_common;