Align HA sysctl values with load-test server config

[agarciamontoro]

Summary

The sysctl block on the High Availability deployment page targets Mattermost server hosts but mirrored the load-test agent (client) values, which are tuned for a different role. Align it with the serverSysctlConfig used by mattermost-load-test-ng to validate large concurrent-user deployments:

• Raise tcp_rmem/tcp_wmem max from 625000 to 2500000 (4x BDP) and expand the comment to describe the autotuning ceiling.
• Raise net.core.{r,w}mem_max from 312500 to 16777216 and dedupe the surrounding comments (mirrors Fix overridden net.core.{r,w}mem_max values mattermost-load-test-ng#987, which removed the redundant double-assignment that set the same keys twice for UDP and TCP).
• Drop rmem_default/wmem_default/tcp_mem, which only belong in the client/agent block and were copied here in error.

Ticket Link

--

[coderabbitai]

📝 Walkthrough

Walkthrough

Documentation update to the high-availability cluster deployment guide. Kernel networking memory parameters for WebSocket connections are increased: tcp_rmem and tcp_wmem to 2500000, net.core.rmem_max and net.core.wmem_max to 16777216, with explanatory comments added.

Changes

Kernel Tuning Documentation

Layer / File(s)	Summary
Tuning Parameters source/administration-guide/scale/high-availability-cluster-based-deployment.rst	Kernel networking memory parameters increased in the "Increase the number of WebSocket connections" section: tcp_rmem and tcp_wmem set to 2500000; net.core.rmem_max and net.core.wmem_max set to 16777216. Clarifying comments added.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: aligning High Availability sysctl configuration values with the load-test server configuration.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description check	✅ Passed	The PR description clearly relates to the changeset, detailing specific sysctl parameter updates and their alignment with load-test server configuration.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix.sysctl.values

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Caution

Failed to replace (edit) comment. This is likely due to insufficient permissions or the comment being deleted.

Error details

{}

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA d05121f

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA 71f3004