diff --git a/api/service/stagedstreamsync/adapter.go b/api/service/stagedstreamsync/adapter.go
index 56c42b661c..41ab8f9569 100644
--- a/api/service/stagedstreamsync/adapter.go
+++ b/api/service/stagedstreamsync/adapter.go
@@ -29,9 +29,10 @@ type syncProtocol interface {
 	RemoveStream(stID sttypes.StreamID) // If a stream delivers invalid data, remove the stream
 	StreamFailed(stID sttypes.StreamID, reason string)
 	SubscribeAddStreamEvent(ch chan<- streammanager.EvtStreamAdded) event.Subscription
+	Streams() []sttypes.Stream
 	NumStreams() int
+	AvailableCapacity() int
 }
-
 type blockChain interface {
 	engine.ChainReader
 	Engine() engine.Engine
diff --git a/api/service/stagedstreamsync/short_range_helper.go b/api/service/stagedstreamsync/short_range_helper.go
index 64ff694432..ad4b184f73 100644
--- a/api/service/stagedstreamsync/short_range_helper.go
+++ b/api/service/stagedstreamsync/short_range_helper.go
@@ -23,10 +23,16 @@ type srHelper struct {
 func (sh *srHelper) getHashChain(ctx context.Context, bns []uint64) ([]common.Hash, []sttypes.StreamID, error) {
 	results := newBlockHashResults(bns)
 
+	concurrency := sh.config.Concurrency
+	availableCapacity := sh.syncProtocol.AvailableCapacity()
+	if concurrency > availableCapacity {
+		concurrency = availableCapacity
+	}
+
 	var wg sync.WaitGroup
-	wg.Add(sh.config.Concurrency)
+	wg.Add(concurrency)
 
-	for i := 0; i != sh.config.Concurrency; i++ {
+	for i := 0; i != concurrency; i++ {
 		go func(index int) {
 			defer wg.Done()