diff --git a/eth/ethconfig/config.go b/eth/ethconfig/config.go
index 4b753242e..254eb152f 100644
--- a/eth/ethconfig/config.go
+++ b/eth/ethconfig/config.go
@@ -71,7 +71,7 @@ var LightClientGPO = gasprice.Config{
 var Defaults = Config{
 	Sync: Sync{
 		UseSnapshots:               false,
-		ExecWorkerCount:            2,
+		ExecWorkerCount:            estimate.ReconstituteState.WorkersHalf(), //only half of CPU, other half will spend for snapshots build/merge/prune
 		ReconWorkerCount:           estimate.ReconstituteState.Workers(),
 		BodyCacheLimit:             256 * 1024 * 1024,
 		BodyDownloadTimeoutSeconds: 30,