diff --git a/internal/utils/fs/limiter.go b/internal/utils/fs/limiter.go
index c08bfd6..5206898 100644
--- a/internal/utils/fs/limiter.go
+++ b/internal/utils/fs/limiter.go
@@ -41,7 +41,7 @@ func (this *Limiter) Ack() {
 }
 
 func (this *Limiter) TryAck() bool {
-	const timeoutDuration = 500 * time.Millisecond
+	const timeoutDuration = 1 * time.Second
 
 	var timeout *time.Timer
 	select {
diff --git a/internal/utils/fs/limiter_test.go b/internal/utils/fs/limiter_test.go
index f54fd4d..67a1ec6 100644
--- a/internal/utils/fs/limiter_test.go
+++ b/internal/utils/fs/limiter_test.go
@@ -4,8 +4,10 @@ package fsutils_test
 
 import (
 	fsutils "github.com/TeaOSLab/EdgeNode/internal/utils/fs"
+	"github.com/TeaOSLab/EdgeNode/internal/utils/testutils"
 	"github.com/iwind/TeaGo/assert"
 	"testing"
+	"time"
 )
 
 func TestLimiter_Ack(t *testing.T) {
@@ -52,3 +54,48 @@ func TestLimiter_TryAck(t *testing.T) {
 		a.IsTrue(limiter.FreeThreads() == 0)
 	}
 }
+
+func TestLimiter_TryAck2(t *testing.T) {
+	if !testutils.IsSingleTesting() {
+		return
+	}
+
+	var a = assert.NewAssertion(t)
+
+	{
+		var limiter = fsutils.NewLimiter(4)
+		var count = limiter.FreeThreads()
+		a.IsTrue(count == 4)
+		for i := 0; i < count-1; i++ {
+			limiter.Ack()
+		}
+		a.IsTrue(limiter.FreeThreads() == 1)
+		a.IsTrue(limiter.TryAck())
+		a.IsFalse(limiter.TryAck())
+		a.IsFalse(limiter.TryAck())
+
+		limiter.Release()
+		a.IsTrue(limiter.TryAck())
+	}
+}
+
+func TestLimiter_Timout(t *testing.T) {
+	var timeout = time.NewTimer(100 * time.Millisecond)
+
+	var r = make(chan bool, 1)
+	r <- true
+
+	var before = time.Now()
+	select {
+	case <-r:
+	case <-timeout.C:
+	}
+	t.Log(time.Since(before).Seconds()*1000, "ms")
+
+	timeout.Stop()
+
+	before = time.Now()
+	timeout.Reset(100 * time.Millisecond)
+	<-timeout.C
+	t.Log(time.Since(before).Seconds()*1000, "ms")
+}
diff --git a/internal/utils/fs/os.go b/internal/utils/fs/os.go
index bc4e0f6..51da4fe 100644
--- a/internal/utils/fs/os.go
+++ b/internal/utils/fs/os.go
@@ -26,6 +26,8 @@ func ReadFile(filename string) (data []byte, err error) {
 }
 
 func WriteFile(filename string, data []byte, perm os.FileMode) (err error) {
+	WriterLimiter.Ack()
 	err = os.WriteFile(filename, data, perm)
+	WriterLimiter.Release()
 	return
 }