diff --git a/source/module/monitor_kernel_lib.c b/source/module/monitor_kernel_lib.c
index 5285807..37b3487 100644
--- a/source/module/monitor_kernel_lib.c
+++ b/source/module/monitor_kernel_lib.c
@@ -1,8 +1,8 @@
 #include "monitor_kernel.h"
 
+#include <linux/interrupt.h>
 #include <linux/sched.h>
 #include <linux/stacktrace.h>
-#include <linux/interrupt.h>
 // #include <linux/sched/task.h>
 // #include <linux/sched/mm.h>
 
@@ -119,10 +119,10 @@ static int init_sa_buffer(void) {
 static void diag_tsk(struct task_struct *p, variable_monitor_task *tsk_info) {
   unsigned int nr_bt;
   // printk(KERN_INFO "diag_tsk\n");
-  diag_task_brief(p, &tsk_info->task); // task brief
-  if (tsk_info->task.sys_task == 1) { // system task
+  diag_task_brief(p, &tsk_info->task);                      // task brief
+  if (tsk_info->task.sys_task == 1) {                       // system task
     nr_bt = diag_task_kern_stack(p, &tsk_info->kern_stack); // kernel stack
-  } else { // other task
+  } else {                                                  // other task
     nr_bt = diag_task_kern_stack(p, &tsk_info->kern_stack); // kernel stack
     dump_proc_chains_argv(1, p, &mm_tree_struct,
                           &tsk_info->proc_chains); // proc chains
@@ -209,6 +209,9 @@ static void clear_all_watch(void) {
 
 static void diag_vm_record(kernel_watch_timer *k_watch_timer,
                            unsigned char is_print) {
+
+  unsigned long long start_time = ktime_get_real();
+
   static variable_monitor_record vm_record;
 
   kernel_watch_arg *kwarg;
@@ -240,8 +243,8 @@ static void diag_vm_record(kernel_watch_timer *k_watch_timer,
 
   if (is_print) {
     printk(KERN_INFO "-----------variable monitor----------\n");
-    printk(KERN_INFO "threshold exceeded, Timestamp %lld, Delay %lld:\n",
-           vm_record.tv, ktime_get_real() - vm_record.tv);
+    printk(KERN_INFO "threshold exceeded, Timestamp %lld, Stack finish Delay %lld:\n",
+           vm_record.tv, start_time - vm_record.tv);
 
     for (i = 0; i < vm_record.threshold_over_count; i++) {
       printk(
@@ -259,7 +262,7 @@ static void diag_vm_record(kernel_watch_timer *k_watch_timer,
   }
 }
 
-void diag_task_by_tgid(pid_t tgid){
+void diag_task_by_tgid(pid_t tgid) {
 
   struct task_struct *tsk;
   int ret;
@@ -275,7 +278,7 @@ void diag_task_by_tgid(pid_t tgid){
   if (!tsk) {
     ret = -EINVAL;
     rcu_read_unlock();
-    return ;
+    return;
   }
 
   diag_variant_buffer_spin_lock(&load_monitor_variant_buffer, flags);
@@ -296,8 +299,8 @@ void diag_task_by_tgid(pid_t tgid){
   rcu_read_unlock();
 }
 
-void diag_task_all(void){
-  pr_info("diag_task_all, tv %lld\n", ktime_get_real());
+void diag_task_all(void) {
+  // pr_info("diag_task_all, tv %lld\n", ktime_get_real());
 
   static variable_monitor_task tsk_info;
 
@@ -328,13 +331,24 @@ void diag_task_all(void){
 
   diag_variant_buffer_spin_unlock(&load_monitor_variant_buffer, flags);
   rcu_read_unlock();
-  pr_info("diag_task_all, finish tv %lld\n", ktime_get_real());
+  // pr_info("diag_task_all, finish tv %lld\n", ktime_get_real());
 }
 
 void diag_task_info(kernel_watch_timer *k_watch_timer) {
   if (k_watch_timer->threshold_over_count <= 0) // if no threshold reached
     return;
-  diag_task_all();
+  pr_info("diag_stack, tv %lld\n", ktime_get_real());
+  if (sample_all) {
+    diag_task_all();
+  } else {
+    int i;
+    kernel_watch_arg *kwarg;
+    for (i = 0; i < k_watch_timer->threshold_over_count; i++) {
+      kwarg = &k_watch_timer->k_watch_args[k_watch_timer->threshold_buffer[i]];
+      diag_task_by_tgid(kwarg->task_id);
+    }
+  }
+  pr_info("diag_stack, finish tv %lld\n", ktime_get_real());
   diag_vm_record(k_watch_timer, 1);
 }
 
@@ -494,9 +508,9 @@ enum hrtimer_restart check_variable_cb(struct hrtimer *timer) {
     k_watch_timer->tv = ktime_get_real();
     pr_info("threshold reached, tv %lld\n", k_watch_timer->tv);
     // highpri_wq
-    // queue_work(system_highpri_wq, &k_watch_timer->wk);
-    diag_task_info(k_watch_timer);
-    
+    queue_work(system_highpri_wq, &k_watch_timer->wk);
+    // diag_task_info(k_watch_timer);
+
     // orig_raise_softirq(MY_SOFTIRQ); // for test
 
     // restart timer after dump_reset_sec sec