cdc: back pressure scan speed (#10142)

[ti-srebot]

cherry-pick #10142 to release-5.0
You can switch your code base to this Pull Request by using git-extras:

# In tikv repo:
git pr https://github.com/tikv/tikv/pull/10151

After apply modifications, you can push your change to this PR via:

git push git@github.com:ti-srebot/tikv.git pr/10151:release-5.0-dfa14c5d23e8

---

What problem does this PR solve?

There will be a series of PRs aims to fix the TiKV CDC OOM issue (too many pending send messages are buffered in memory).

To resolve the issue, we have two strategies,

1. Limit the speed of producing messages during the initial scan stage. cdc: limit scan speed #9948
2. Set an upper bound of pending send messages. cdc: flow control #9885

The series of PRs adopts both strategies.

This is part of #9885, it backpressure scan speed by replacing an unbounded channel with a bounded channel.

Also, this PR cherry-picks #10028.

Plan:

• take1: cherry-pick speed limiter. cdc: limit scan speed #10108
• take2: set an upper bound of an internal channel used in CDC <-- we are here.
• take3: add memory quota to CDC and kill connection if it uses too much memory.
• take4: cherry-pick other bugfixes in cdc: flow control #9885

See full changes: master...overvenus:cdc/flowcontrol/all

Cc #8168 #9996

Check List

Tests

• Unit test
• Integration test

Release note

• Support back pressure CDC scan speed.
• Fix interference between connections to the same region.

[ti-srebot]

/run-all-tests

[ti-srebot]

@overvenus you're already a collaborator in bot's repo.

[overvenus]

/run-test

test_region_heartbeat_report_approximate_size fails.

[overvenus]

/run-test

test_region_heartbeat_report_approximate_size fails

[5kbpers]

Suggested change

// fn broadcast(&self, change_data_event: Event, normal_only: bool) {

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• 5kbpers
• amyangfei

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

The full list of commands accepted by this bot can be found here.

Reviewer can indicate their review by writing /lgtm in a comment.
Reviewer can cancel approval by writing /lgtm cancel in a comment.

[overvenus]

/merge

[ti-chi-bot]

@overvenus: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

If you have any questions about the PR merge process, please refer to pr process.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[ti-chi-bot]

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

Commit hash: 3070b48

[ti-chi-bot]

@ti-srebot: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.