diff --git a/src/runtime/mgcwork.go b/src/runtime/mgcwork.go
index 41edb48954..b05b06a1de 100644
--- a/src/runtime/mgcwork.go
+++ b/src/runtime/mgcwork.go
@@ -7,8 +7,8 @@ package runtime
 import "unsafe"
 
 const (
-	_Debugwbufs  = false   // if true check wbufs consistency
-	_WorkbufSize = 1 * 256 // in bytes - if small wbufs are passed to GC in a timely fashion.
+	_Debugwbufs  = false // if true check wbufs consistency
+	_WorkbufSize = 4096  // in bytes; larger values result in less contention
 )
 
 // Garbage collector work pool abstraction.