*: query-status -s and purge-relay send to all relay worker

[lance6716]

What problem does this PR solve?

query-status -s and purge-relay send to all relay worker

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test

Code changes

Side effects

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation
• Need to be included in the release note

[lance6716]

CI failed because master discover offline worker too late https://internal.pingcap.net/idc-jenkins/blue/organizations/jenkins/dm_ghpr_test/detail/dm_ghpr_test/8756/pipeline/76/ :

(locally test)
worker2: [2021/04/08 10:38:25.886 +08:00] [INFO] [main.go:92] ["dm-worker exit"]
master3 (leader): [2021/04/08 10:39:09.994 +08:00] [INFO] [scheduler.go:1321] ["receive worker status change event"] [component=scheduler] [delete=true] [event="{"worker-name":"worker2","join-time":"0001-01-01T00:00:00Z"}"]

[lance6716]

CI failed:

I don't know why there's only one "Welcome to dm-worker" in worker4.log, but

[2021-04-08T03:22:51.586Z] [2021/04/08 11:22:29.931 +08:00] [INFO] [main.go:84] ["got signal to exit"] [signal=terminated]
[2021-04-08T03:22:51.586Z] [2021/04/08 11:22:30.354 +08:00] [INFO] [main.go:92] ["dm-worker exit"]
[2021-04-08T03:22:51.586Z] [2021/04/08 11:22:30.380 +08:00] [INFO] [main.go:84] ["got signal to exit"] [signal=terminated]

[lichunzhu]

/lgtm

[lance6716]

/run-all-tests

[lance6716]

success CI

• https://internal.pingcap.net/idc-jenkins/blue/organizations/jenkins/dm_ghpr_test/detail/dm_ghpr_test/8760/pipeline/76
• https://internal.pingcap.net/idc-jenkins/blue/organizations/jenkins/dm_ghpr_test/detail/dm_ghpr_test/8761/pipeline
• https://internal.pingcap.net/idc-jenkins/blue/organizations/jenkins/dm_ghpr_test/detail/dm_ghpr_test/8762/pipeline

I'll re-run many times to check if it's fixed.

[lance6716]

/run-all-tests

[lance6716]

/run-all-tests

[lance6716]

@GMHDBJD PTAL

[GMHDBJD]

/lgtm

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• GMHDBJD
• lichunzhu

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[lance6716]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 0e08bad

[ti-srebot]

cherry pick to release-2.0 in PR #1570