From 64b244207c57b2c49aa37b180daff8c7d54dc839 Mon Sep 17 00:00:00 2001
From: ryjiang <shanghaikid@users.noreply.github.com>
Date: Wed, 17 Nov 2021 15:59:21 +0800
Subject: [PATCH] [skip ci]Update  chap06_root_coordinator.md (#11944)

Signed-off-by: ruiyi.jiang <ruiyi.jiang@zilliz.com>
---
 docs/developer_guides/chap06_root_coordinator.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/docs/developer_guides/chap06_root_coordinator.md b/docs/developer_guides/chap06_root_coordinator.md
index cc9285e113..e9b52e89a4 100644
--- a/docs/developer_guides/chap06_root_coordinator.md
+++ b/docs/developer_guides/chap06_root_coordinator.md
@@ -697,6 +697,11 @@ type timetickSync struct {
 	lock          sync.Mutex
 	proxyTimeTick map[typeutil.UniqueID]*channelTimeTickMsg
 	sendChan      chan map[typeutil.UniqueID]*channelTimeTickMsg
+
+	// record ddl timetick info
+	ddlLock  sync.RWMutex
+	ddlMinTs typeutil.Timestamp
+	ddlTsSet map[typeutil.Timestamp]struct{}
 }
 
 func newTimeTickSync(core *Core) *timetickSync