Expand High CPU Troubleshooting

[stefnestor]

Summary

👋 Ports High CPU article to docs.

🙋‍♀️

1. Should have Dev sign-off.
2. allocated_processors in CAT nodes isn't available till v9.3.0 per this, (how) do we mark that?

Related understanding for top summary portion changes from

• Node Tasks API Report Thread Pool elasticsearch#138935
• Hot Threads | Report Task ID elasticsearch#127847

🙏 TIA!

Generative AI disclosure

1. Did you use a generative AI (GenAI) tool to assist in creating this contribution?

• Yes
• No

[github-actions]

Vale Linting Results

Summary: 1 warning, 5 suggestions found

⚠️ Warnings (1)

File	Line	Rule	Message
troubleshoot/elasticsearch/high-cpu-usage.md	176	Elastic.BritishSpellings	Use American English spelling 'behavior' instead of British English 'behaviour'.

💡 Suggestions (5)

File	Line	Rule	Message
troubleshoot/elasticsearch/high-cpu-usage.md	17	Elastic.Wordiness	Consider using 'all' instead of 'all of '.
troubleshoot/elasticsearch/high-cpu-usage.md	112	Elastic.Acronyms	'JVM' has no definition.
troubleshoot/elasticsearch/high-cpu-usage.md	114	Elastic.Acronyms	'JVM' has no definition.
troubleshoot/elasticsearch/high-jvm-memory-pressure.md	21	Elastic.Acronyms	'JVM' has no definition.
troubleshoot/elasticsearch/task-queue-backlog.md	153	Elastic.WordChoice	Consider using 'refer to (if it's a document), view (if it's a UI element)' instead of 'see', unless the term is in the UI.

[kilfoyle]

Suggested change

	* Share only after receiving any necessary business approvals as this file might contain private information. Files are handled according to [Elastic's privacy statement](https://www.elastic.co/legal/privacy-statement).
	* Share this file only after receiving any necessary business approvals as it might contain private information. Files are handled according to [Elastic's privacy statement](https://www.elastic.co/legal/privacy-statement).

[kilfoyle]

Suggested change

	* [Monitor Slow Logs](#diagnose-task-slow-logs)
	* [Monitor slow logs](#diagnose-task-slow-logs)

[kilfoyle]

Suggested change

	### Monitor Slow Logs [diagnose-task-slow-logs]
	### Monitor slow logs [diagnose-task-slow-logs]

[kilfoyle]

Suggested change

	If you're not present during incident to investigate backlogged tasks, you might consider enabling [Slow Logs](elasticsearch://reference/elasticsearch/index-settings/slow-log.md) to review later.
	If you're not present during an incident to investigate backlogged tasks, you might consider enabling [slow logs](elasticsearch://reference/elasticsearch/index-settings/slow-log.md) to review later.

[kilfoyle]

LGTM! 🦘

@stefnestor this is superb! Very, very nice work. The organization here is so much better than what we had before. I added lots of comments but they're all just minor phrasing things.

---

"allocated_processors in CAT nodes isn't available till v9.3.0 per elastic/elasticsearch#134692, (how) do we mark that?"

This suggestion (below) will add an "applies_to" tag to mark 9.3 GA.

[kilfoyle]

LGTM! 🦖
Thanks Stef!!! What a nice improvement for our docs.

[stefnestor]

Cheers, @kilfoyle! Thanks for your help on this!

The very top part of CPU-vs-Java-vs-threads needs an ES Dev sign-off. I will request in Slack but please LMK if your team has a Github way of directing this to them 🙏

[kilfoyle]

The very top part of CPU-vs-Java-vs-threads needs an ES Dev sign-off. I will request in Slack but please LMK if your team has a Github way of directing this to them 🙏

Sounds good! There are several elastic/es-* groups that we can tag in the reviewers part of the PR, but unfortunately I have no idea which of those teams is the right one to review. So I think Slack is the best bet.