domain: increase TTL to reduce the occurrence of reporting min startT…

…S errors (pingcap#12578)

domain/domain.go

@@ -421,7 +421,7 @@ func (do *Domain) topNSlowQueryLoop() {
 func (do *Domain) infoSyncerKeeper() {
 	defer do.wg.Done()
 	defer recoverInDomain("infoSyncerKeeper", false)
-	ticker := time.NewTicker(time.Second * time.Duration(infosync.InfoSessionTTL) / 2)
+	ticker := time.NewTicker(infosync.ReportInterval)
 	defer ticker.Stop()
 	for {
 		select {

domain/infosync/info.go

@@ -43,14 +43,15 @@ const (
 	// ServerMinStartTSPath store the server min start timestamp.
 	ServerMinStartTSPath = "/tidb/server/minstartts"
 	// keyOpDefaultRetryCnt is the default retry count for etcd store.
-	keyOpDefaultRetryCnt = 2
+	keyOpDefaultRetryCnt = 5
 	// keyOpDefaultTimeout is the default time out for etcd store.
 	keyOpDefaultTimeout = 1 * time.Second
+	// InfoSessionTTL is the ETCD session's TTL in seconds.
+	InfoSessionTTL = 10 * 60
+	// ReportInterval is interval of infoSyncerKeeper reporting min startTS.
+	ReportInterval = 30 * time.Second
 )
 
-// InfoSessionTTL is the etcd session's TTL in seconds. It's exported for testing.
-var InfoSessionTTL = 1 * 60
-
 // InfoSyncer stores server info to etcd when the tidb-server starts and delete when tidb-server shuts down.
 type InfoSyncer struct {
 	etcdCli        *clientv3.Client