diff --git a/src/pkg/net/protoconn_test.go b/src/pkg/net/protoconn_test.go
index b59925e01c..7e4fbdaa74 100644
--- a/src/pkg/net/protoconn_test.go
+++ b/src/pkg/net/protoconn_test.go
@@ -103,6 +103,7 @@ func TestTCPConnSpecificMethods(t *testing.T) {
 	}
 	defer c.Close()
 	c.SetKeepAlive(false)
+	c.SetKeepAlivePeriod(3 * time.Second)
 	c.SetLinger(0)
 	c.SetNoDelay(false)
 	c.LocalAddr()