diff --git a/blobstore/blobnode/core/blobfile_test.go b/blobstore/blobnode/core/blobfile_test.go
index 4771d4e0d..3b543ce94 100644
--- a/blobstore/blobnode/core/blobfile_test.go
+++ b/blobstore/blobnode/core/blobfile_test.go
@@ -30,32 +30,21 @@ import (
 	"github.com/cubefs/cubefs/blobstore/util/taskpool"
 )
 
-func TestBlobFile_Op(t *testing.T) {
-	testDir, err := os.MkdirTemp(os.TempDir(), "BlobFileOp")
-	require.NoError(t, err)
-	defer os.RemoveAll(testDir)
-
-	posixfilepath := filepath.Join(testDir, "PoxsixFile")
-	log.Info(posixfilepath)
-
-	temppath := filepath.Join(posixfilepath, "xxxtemp")
-	f, err := OpenFile(temppath, false)
-	require.Error(t, err)
-	require.Nil(t, f)
-
-	f, err = OpenFile(posixfilepath, true)
-	require.NoError(t, err)
-
-	require.NotNil(t, f)
-
+func doBlobFileOp(t *testing.T, f *os.File, emptyIoPool bool) {
 	// create
 	syncWorker := mergetask.NewMergeTask(-1, func(interface{}) error { return nil })
 
-	ctr := gomock.NewController(t)
-	ioPool := mocks.NewMockIoPool(ctr)
-	ioPool.EXPECT().Submit(gomock.Any()).Do(func(args taskpool.IoPoolTaskArgs) {
-		args.TaskFn()
-	}).AnyTimes()
+	ioPool := taskpool.NewReadPool(0, 0, taskpool.IoPoolMetricConf{})
+
+	if !emptyIoPool {
+		ctr := gomock.NewController(t)
+		ioPool = mocks.NewMockIoPool(ctr)
+		ioPool.(*mocks.MockIoPool).EXPECT().Submit(gomock.Any()).Do(func(args taskpool.IoPoolTaskArgs) {
+			args.TaskFn()
+		}).AnyTimes()
+		// ioPool.EXPECT().IsEmpty().Return(emptyIoPool).AnyTimes()
+	}
+
 	ioPools := map[qos.IOTypeRW]taskpool.IoPool{
 		qos.IOTypeRead:  ioPool,
 		qos.IOTypeWrite: ioPool,
@@ -141,6 +130,35 @@ func TestBlobFile_Op(t *testing.T) {
 	require.Equal(t, int(stat.Blocks), 0)
 }
 
+func TestBlobFile_Op(t *testing.T) {
+	testDir, err := os.MkdirTemp(os.TempDir(), "BlobFileOp")
+	require.NoError(t, err)
+	defer os.RemoveAll(testDir)
+
+	posixfilepath := filepath.Join(testDir, "PoxsixFile")
+	log.Info(posixfilepath)
+
+	temppath := filepath.Join(posixfilepath, "xxxtemp")
+	f, err := OpenFile(temppath, false)
+	require.Error(t, err)
+	require.Nil(t, f)
+
+	f, err = OpenFile(posixfilepath, true)
+	require.NoError(t, err)
+	require.NotNil(t, f)
+
+	// enable io pools
+	doBlobFileOp(t, f, false)
+
+	// invalid/empty io pools
+	posixfilepath2 := filepath.Join(testDir, "PoxsixFile2")
+	f, err = OpenFile(posixfilepath2, true)
+	require.NoError(t, err)
+	require.NotNil(t, f)
+
+	doBlobFileOp(t, f, true)
+}
+
 func TestBlobFile_doTaskFnCtxCancel(t *testing.T) {
 	testDir, err := os.MkdirTemp(os.TempDir(), "BlobFileTaskCancel")
 	require.NoError(t, err)
@@ -164,6 +182,7 @@ func TestBlobFile_doTaskFnCtxCancel(t *testing.T) {
 
 	ctr := gomock.NewController(t)
 	ioPool := mocks.NewMockIoPool(ctr)
+	// ioPool.EXPECT().IsEmpty().Return(false).AnyTimes()
 	ioPools := map[qos.IOTypeRW]taskpool.IoPool{
 		qos.IOTypeRead:  ioPool,
 		qos.IOTypeWrite: ioPool,
diff --git a/blobstore/blobnode/core/config.go b/blobstore/blobnode/core/config.go
index 85409875f..b51cd9d3d 100644
--- a/blobstore/blobnode/core/config.go
+++ b/blobstore/blobnode/core/config.go
@@ -153,9 +153,9 @@ func InitConfig(conf *Config) error {
 		conf.AllowCleanTrash = true
 	}
 
-	defaulter.LessOrEqual(&conf.WriteThreadCnt, defaultWriteThreadCnt)
-	defaulter.LessOrEqual(&conf.ReadThreadCnt, defaultReadThreadCnt)
-	defaulter.LessOrEqual(&conf.DeleteThreadCnt, defaultDeleteThreadCnt)
+	defaulter.Equal(&conf.WriteThreadCnt, defaultWriteThreadCnt)
+	defaulter.Equal(&conf.ReadThreadCnt, defaultReadThreadCnt)
+	defaulter.Equal(&conf.DeleteThreadCnt, defaultDeleteThreadCnt)
 
 	conf.DataQos.WriteChanQueCnt = int32(conf.WriteThreadCnt)
 	qos.InitAndFixQosConfig(&conf.DataQos)
diff --git a/blobstore/util/taskpool/iopool.go b/blobstore/util/taskpool/iopool.go
index 6b34dedca..081919e55 100644
--- a/blobstore/util/taskpool/iopool.go
+++ b/blobstore/util/taskpool/iopool.go
@@ -95,6 +95,11 @@ func NewDeletePool(threadCnt, queueDepth int, conf IoPoolMetricConf) IoPool {
 // $threadCnt: The number of read/write work goroutine, it must be greater than $chanCnt
 // $queueDepth: The number of elements in the queue
 func newCommonIoPool(chanCnt, threadCnt, queueDepth int, conf IoPoolMetricConf) *ioPoolSimple {
+	if threadCnt <= 0 || chanCnt <= 0 || queueDepth <= 0 {
+		// empty io pool, dont limit
+		return &ioPoolSimple{closed: make(chan struct{})}
+	}
+
 	iopoolMetric := prometheus.NewSummaryVec(
 		prometheus.SummaryOpts{
 			Namespace:  conf.Namespace,
@@ -175,6 +180,11 @@ func (p *ioPoolSimple) reportMetric(opStage string, tm time.Time) {
 }
 
 func (p *ioPoolSimple) Submit(args IoPoolTaskArgs) {
+	if p.notLimit() {
+		args.TaskFn()
+		return
+	}
+
 	idx, task := p.generateTask(args)
 
 	// if ctx has been cancelled, try to avoid enqueuing as much as possible;
@@ -238,3 +248,8 @@ func (p *ioPoolSimple) Close() {
 
 	log.Info("close all io pool, exit")
 }
+
+func (p *ioPoolSimple) notLimit() bool {
+	// dont limit: queue is empty
+	return p.queue == nil
+}
diff --git a/blobstore/util/taskpool/iopool_test.go b/blobstore/util/taskpool/iopool_test.go
index b3e1219f2..b2dd3907b 100644
--- a/blobstore/util/taskpool/iopool_test.go
+++ b/blobstore/util/taskpool/iopool_test.go
@@ -13,6 +13,7 @@ import (
 )
 
 func TestIoPoolSimple(t *testing.T) {
+	// normal
 	metricConf := IoPoolMetricConf{
 		ClusterID: 1,
 		IDC:       "idc",
@@ -241,4 +242,33 @@ func TestIoPoolSimple(t *testing.T) {
 		require.NoError(t, err)
 		require.Equal(t, 1, n) // long time task, not raw data
 	}
+
+	// empty, not limit write
+	emptyPool := newCommonIoPool(0, 0, 0, IoPoolMetricConf{})
+	require.True(t, emptyPool.notLimit())
+	defer emptyPool.Close()
+
+	n := 0
+	data := []byte(content)
+	task := IoPoolTaskArgs{
+		TaskFn: func() { n, err = file.WriteAt(data, 0) },
+	}
+
+	emptyPool.Submit(task)
+	require.NoError(t, err)
+	require.Equal(t, len(content), n)
+
+	// empty, not limit read
+	n = 0
+	data = make([]byte, len(content))
+	task = IoPoolTaskArgs{
+		TaskFn: func() { n, err = file.ReadAt(data, 0) },
+	}
+	require.Equal(t, uint8(0), data[0])
+	require.Equal(t, 0, n)
+
+	emptyPool.Submit(task)
+	require.NoError(t, err)
+	require.Equal(t, len(content), n)
+	require.Equal(t, content, string(data))
 }