diff --git a/job.go b/job.go
index 88f3824..cb33e8b 100644
--- a/job.go
+++ b/job.go
@@ -167,15 +167,13 @@ func (j *Job) limit() bool {
 		return false
 	}
 
-	// 更精确的控制是加锁
-	// 两次运行时间极为接近的任务才可能出现控制不精确的情况
-	count := atomic.LoadInt64(j.Count)
-	if j.Parallels <= count {
+	count := atomic.AddInt64(j.Count, 1)
+	if j.Parallels < count {
+		atomic.AddInt64(j.Count, -1)
 		j.Fail(time.Now(), fmt.Sprintf("job[%s] running on[%s] running:[%d]", j.Key(), j.runOn, count))
 		return true
 	}
 
-	atomic.AddInt64(j.Count, 1)
 	return false
 }