diff --git a/client/operation.go b/client/operation.go
index 362613a..31d6793 100644
--- a/client/operation.go
+++ b/client/operation.go
@@ -369,6 +369,7 @@ func (hc *houstonClient) launch(meta *procmeta) error {
 	meta.cmd.Env = append(meta.cmd.Env, fmt.Sprintf("HOUSTON_SIBLIING_INDEX=%d", index))
 	err = meta.cmd.Start()
 	if err == nil {
+		logger.Println("process index, pid =", index, meta.cmd.Process.Pid)
 		set_affinity(meta.cmd.Process.Pid, index)
 		meta.setState(protos.ProcessState_Running)
 	}