*: Add sysvar tidb_tso_client_rpc_mode for setting TSO RPC concurrency

[MyonKeminta]

What problem does this PR solve?

Issue Number: close #54960

Requires: tikv/pd#8633

Problem Summary:

What changed and how does it work?

• Update pd client to support concurrent TSO RPC
• Add sysvar tidb_tso_client_rpc_mode for setting TSO RPC concurrency
• Add some metrics to the grafana dashboard that would be helpful for concurrent TSO RPC.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

Add support for multiple TSO RPC requests to be done in parallel. `tidb_tso_client_rpc_mode` is now available for enabling this feature, to reduce GetTS latency, at the expense of higher ops of TSO RPC.

[ti-chi-bot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[tiprow]

Hi @MyonKeminta. Thanks for your PR.

PRs from untrusted users cannot be marked as trusted with /ok-to-test in this repo meaning untrusted PR authors can never trigger tests themselves. Collaborators can still trigger tests on the PR using /test all.

I understand the commands that are listed here.

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 kubernetes-sigs/prow repository.

[ti-chi-bot]

@joey-yez: adding LGTM is restricted to approvers and reviewers in OWNERS files.

In response to this:

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 kubernetes/test-infra repository.

[codecov]

Codecov Report

Attention: Patch coverage is 52.63158% with 9 lines in your changes missing coverage. Please review.

Project coverage is 76.0544%. Comparing base (1b4b2f0) to head (697df1e).
Report is 1 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #56292        +/-   ##
================================================
+ Coverage   73.3264%   76.0544%   +2.7280%     
================================================
  Files          1619       1641        +22     
  Lines        446472     454627      +8155     
================================================
+ Hits         327382     345764     +18382     
+ Misses        99034      87329     -11705     
- Partials      20056      21534      +1478     

Flag	Coverage Δ
integration	51.9523% <52.6315%> (?)
unit	72.4563% <52.6315%> (-0.0602%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.9478% <ø> (ø)
parser	∅ <ø> (∅)
br	62.9846% <ø> (+17.9518%)	⬆️

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-26 04:21:39.488109524 +0000 UTC m=+1712569.228533456: ☑️ agreed by crazycs520.
• 2024-09-26 04:41:36.546963328 +0000 UTC m=+1713766.287387268: ☑️ agreed by ekexium.

[MyonKeminta]

/test check-dev2

[tiprow]

@MyonKeminta: Cannot trigger testing until a trusted user reviews the PR and leaves an /ok-to-test message.

In response to this:

/test check-dev2

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 kubernetes-sigs/prow repository.

[yudongusa]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: crazycs520, ekexium, joey-yez, tangenta, yudongusa

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [crazycs520,ekexium,tangenta]
• pkg/domain/OWNERS [tangenta]
• pkg/sessionctx/variable/OWNERS [yudongusa]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[MyonKeminta]

/merge

[ti-chi-bot]

@MyonKeminta: We have migrated to builtin LGTM and approve plugins for reviewing.

👉 Please use /approve when you want approve this pull request.

The changes announcement: LGTM plugin changes

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.