diff --git a/judge/tasks/submission.py b/judge/tasks/submission.py
index aa474f8..1c39b1c 100644
--- a/judge/tasks/submission.py
+++ b/judge/tasks/submission.py
@@ -1,6 +1,7 @@
 from celery import shared_task
 from django.core.cache import cache
 from django.utils.translation import gettext as _
+from time import sleep
 
 from judge.models import Problem, Profile, Submission
 from judge.utils.celery import Progress
@@ -34,6 +35,7 @@ def rejudge_problem_filter(
         for submission in queryset.iterator():
             submission.judge(rejudge=True, batch_rejudge=True)
             rejudged += 1
+            sleep(0.1)
             if rejudged % 10 == 0:
                 p.done = rejudged
     return rejudged