diff --git a/openvj/settings.py b/openvj/settings.py
index 53ee7f5..ea986bb 100644
--- a/openvj/settings.py
+++ b/openvj/settings.py
@@ -121,7 +121,8 @@ STATIC_URL = '/static/'
 
 CELERY_ROUTES = {
     'server.tasks.submit_dispatcher': {'queue': 'local'},
-    'server.tasks.release_robot_user': {'queue': 'local'},
+    'server.tasks.submit_waiting_submission': {'queue': 'local'},
     'server.tasks.update_submission': {'queue': 'local'},
-    'server.tasks.get_problem': {'queue': 'robot'}
+    'server.tasks.get_problem': {'queue': 'robot'},
+    'server.tasks.submit': {'queue': 'robot'},
 }
diff --git a/server/admin.py b/server/admin.py
index 743ad1f..cb2c3c2 100644
--- a/server/admin.py
+++ b/server/admin.py
@@ -42,6 +42,7 @@ admin.site.register(Problem, ProblemAdmin)
 
 class SubmissionAdmin(admin.ModelAdmin):
     list_display = ["api_key", "problem", "language", "result", "create_time", "status"]
+    ordering = ["create_time"]
 
 admin.site.register(Submission, SubmissionAdmin)
 
diff --git a/server/tasks.py b/server/tasks.py
index 946d702..79a85c2 100644
--- a/server/tasks.py
+++ b/server/tasks.py
@@ -5,7 +5,7 @@ import json
 
 from openvj import celery_app
 from robots.utils import Result
-from .models import RobotUserStatus, SubmissionStatus
+from .models import RobotUserStatus, SubmissionStatus, SubmissionWaitingQueue
 
 
 # remote robot task
@@ -17,7 +17,6 @@ def get_problem(robot, url):
 # remote robot task
 @celery_app.task
 def submit(robot, robot_user, submit_url, origin_id, language, code):
-    print("submit")
     try:
         origin_submission_id = robot.submit(submit_url, language, code, origin_id)
     except Exception as e:
@@ -28,7 +27,6 @@ def submit(robot, robot_user, submit_url, origin_id, language, code):
     time.sleep(2)
     retries = 20
     while retries:
-        print("retry", retries)
         try:
             result = robot.get_result(origin_submission_id, robot_user.username)
         except Exception as e:
@@ -43,11 +41,24 @@ def submit(robot, robot_user, submit_url, origin_id, language, code):
             "origin_submission_id": origin_submission_id}
 
 
+def release_robot_user(robot_user):
+    robot_user.status = RobotUserStatus.free
+    robot_user.save(update_fields=["status"])
+
+
 # local task
 @celery_app.task
-def release_robot_user(submit_result, robot_user):
-    robot_user.status = RobotUserStatus.free
-    robot_user.save()
+def submit_waiting_submission(submit_result, problem, robot, robot_user):
+    waiting_queue = SubmissionWaitingQueue.objects.all().order_by("create_time")
+    if waiting_queue.exists():
+        queue_head = waiting_queue.first()
+        submission = queue_head.submission
+        task_id = submit_dispatcher.delay(problem, submission, robot_user, robot).id
+        submission.task_id = task_id
+        submission.save(update_fields=["task_id"])
+        queue_head.delete()
+    else:
+        release_robot_user(robot_user)
 
 
 # local task
@@ -59,18 +70,17 @@ def update_submission(submit_result, submission):
     submission.memory = submit_result["memory"]
     submission.info = json.dumps(submit_result["info"])
     submission.status = SubmissionStatus.done
-    print("updated")
     submission.save(update_fields=["origin_submission_id", "result", "cpu_time", "memory", "info", "status"])
 
 
 # local task
 @celery_app.task
 def submit_dispatcher(problem, submission, robot_user, robot):
-    task_id = submit.apply_async((robot, robot_user, problem.submit_url, problem.origin_id,
-                                  submission.language, submission.code),
+    task_id = submit.apply_async(args=(robot, robot_user, problem.submit_url, problem.origin_id,
+                                       submission.language, submission.code),
                                  # link相当于执行成功后的回调函数
-                                 link=[release_robot_user.s(robot_user)])
+                                 link=[submit_waiting_submission.s(problem, robot, robot_user),
+                                       update_submission.s(submission)]).id
     submission.robot_user = robot_user
     submission.submit_task_id = task_id
-    print(task_id)
     submission.save(update_fields=["submit_task_id", "robot_user"])