From ba6a5c99ed4bcbd18bced968fb66fa01ea28239a Mon Sep 17 00:00:00 2001
From: Ti Chi Robot <ti-community-prow-bot@tidb.io>
Date: Mon, 11 Dec 2023 13:07:47 +0800
Subject: [PATCH] cdc: fixes minor bugs #10168 and #10169 (#10170) (#10189)

close pingcap/tiflow#10168
---
 cdc/kv/client.go                   | 4 ++++
 cdc/processor/sinkmanager/tasks.go | 4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/cdc/kv/client.go b/cdc/kv/client.go
index dc8822a0e63..bde714df5de 100644
--- a/cdc/kv/client.go
+++ b/cdc/kv/client.go
@@ -73,6 +73,8 @@ const (
 	regionScheduleReload = false
 
 	resolveLockMinInterval = 10 * time.Second
+
+	scanRegionsConcurrency = 1024
 )
 
 // time interval to force kv client to terminate gRPC stream and reconnect
@@ -432,6 +434,8 @@ func (s *eventFeedSession) eventFeed(ctx context.Context) error {
 	g.Go(func() error { return s.logSlowRegions(ctx) })
 
 	g.Go(func() error {
+		g, ctx := errgroup.WithContext(ctx)
+		g.SetLimit(scanRegionsConcurrency)
 		for {
 			select {
 			case <-ctx.Done():
diff --git a/cdc/processor/sinkmanager/tasks.go b/cdc/processor/sinkmanager/tasks.go
index c6b6ea8757b..a736b6fca50 100644
--- a/cdc/processor/sinkmanager/tasks.go
+++ b/cdc/processor/sinkmanager/tasks.go
@@ -33,8 +33,8 @@ var (
 	maxUpdateIntervalSize = defaultMaxUpdateIntervalSize
 
 	// Sink manager schedules table tasks based on lag. Limit the max task range
-	// can be helpful to reduce changefeed latency.
-	maxTaskRange = 5 * time.Second
+	// can be helpful to reduce changefeed latency for large initial data.
+	maxTaskRange = 30 * time.Minute
 )
 
 // Used to record the progress of the table.