When DM synchronizes DDL, secondsBehindMaster is 0

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Original topic: DM同步DDL时,secondsBehindMaster为0

| username: liujia

[TiDB Usage Environment] Production Environment
[TiDB Version] 5.3.0
[Reproduction Path] DM synchronizes a large table from MySQL to TiDB. After executing DDL on MySQL, check the status of DM, and secondsBehindMaster is 0.

[Attachment: Screenshot/Log/Monitoring]

| username: 这里介绍不了我 | Original post link

It seems like it hasn’t caught up, but I see that your two GTIDs are consistent.

| username: liujia | Original post link

Inconsistent, look at the front.

| username: Lucien-卢西恩 | Original post link

Check if the downstream TiDB is currently executing DDL and investigate whether the DDL status is normal. DDL 语句的执行原理及最佳实践 | PingCAP 文档中心
Use DM troubleshooting methods to locate the current logs and monitoring situation.
TiDB Data Migration 性能问题及处理方法 | PingCAP 文档中心

| username: 小于同学 | Original post link

Check if there are any issues in the logs.