diff --git a/APP_Framework/Framework/transform_layer/xizi/user_api/posix_support/pthread.c b/APP_Framework/Framework/transform_layer/xizi/user_api/posix_support/pthread.c
index 924b39179..90a163d48 100644
--- a/APP_Framework/Framework/transform_layer/xizi/user_api/posix_support/pthread.c
+++ b/APP_Framework/Framework/transform_layer/xizi/user_api/posix_support/pthread.c
@@ -33,7 +33,7 @@ int pthread_create(pthread_t *thread, const pthread_attr_t *attr,
 
     if (NULL == attr) {
         task.prio = KTASK_PRIORITY_MAX / 2;
-        task.stack_size = 1024 ;
+        task.stack_size = 4096 ;
     } else {
         task.prio = attr->schedparam.sched_priority ;
         task.stack_size = attr->stacksize ;
diff --git a/Ubiquitous/XiZi/kernel/thread/mutex.c b/Ubiquitous/XiZi/kernel/thread/mutex.c
index 88c1177a9..9428a853d 100644
--- a/Ubiquitous/XiZi/kernel/thread/mutex.c
+++ b/Ubiquitous/XiZi/kernel/thread/mutex.c
@@ -114,7 +114,7 @@ static int32 _MutexObtain(struct Mutex *mutex, int32 msec)
                     KTaskPrioSet(mutex->holder->id.id, task->task_dync_sched_member.cur_prio);
                 }
 
-                LinklistSuspend(&(mutex->pend_list), task, LINKLIST_FLAG_PRIO);
+                LinklistSuspend(&(mutex->pend_list), task, LINKLIST_FLAG_FIFO);
 
                 if (wait_time > 0) {
                     SYS_KDEBUG_LOG(KDBG_IPC,
diff --git a/Ubiquitous/XiZi/kernel/thread/semaphore.c b/Ubiquitous/XiZi/kernel/thread/semaphore.c
index ac6f6eeb3..4bd745beb 100644
--- a/Ubiquitous/XiZi/kernel/thread/semaphore.c
+++ b/Ubiquitous/XiZi/kernel/thread/semaphore.c
@@ -120,7 +120,7 @@ static int32 _SemaphoreObtain(struct Semaphore *sem, int32 msec)
     SYS_KDEBUG_LOG(KDBG_IPC, ("obtain semaphore: suspending task %s\n",
             GetKTaskDescriptor()->task_base_info.name));
 
-    LinklistSuspend(&sem->pend_list, task, LINKLIST_FLAG_PRIO);
+    LinklistSuspend(&sem->pend_list, task, LINKLIST_FLAG_FIFO);
 
     if (wait_time > 0) {
          KTaskSetDelay(task, wait_time);