Enable /debug/pprof/heap

[CalvinNeo]

What is changed and how it works?

Issue Number: Close #xxx

1. While prof.activate is set to true, calling prof.dump will dump a heap file.
2. The heap file can be transformed into svg format with the help from jeprof.
3. TiFlash Proxy(TiKV) will embed a jeprof.in into its own code.
4. When /debug/pprof/heap?jeprof=true is called, a perl sub-process is started with perl /dev/stdin --show_byte ${tiflash_path} ${heap_file_path} --svg.
5. perl will execute the embedded script, and print the transformed svg files in stdout.

NOTE

1. jeprof.in is not released to user.
2. On some deployments, there could be insufficient privilege, so the API could fail and return to user with detailed message.
3. perl must be provided, otherwise the API could fail and return to user with detailed message.

What's Changed:

Enable /debug/pprof/heap

Related changes

• PR to update pingcap/docs/pingcap/docs-cn:
• Need to cherry-pick to the release branch

Check List

Tests

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

Side effects

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

Release note

Support ad-hoc heap profiling

[CalvinNeo]

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: JaySon-Huang

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• HACKED_OWNERS [JaySon-Huang]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-07-31 07:05:43.484418188 +0000 UTC m=+339459.764466256: ☑️ agreed by JaySon-Huang.