Clarify TiKV large-row limit in transaction restraints (#23338)

[ti-chi-bot]

This is an automated cherry-pick of #23338

What is changed, added or deleted? (Required)

Clarify in develop/dev-guide-transaction-restraints.md that increasing the TiDB large-row limit alone is not enough. When a single write request exceeds TiKV raftstore.raft-entry-max-size, TiKV rejects the request, so users need to adjust the TiKV limit together with the TiDB row-size limit.

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• v6.5 (TiDB 6.5 versions)
• v6.1 (TiDB 6.1 versions)
• v5.4 (TiDB 5.4 versions)
• v5.3 (TiDB 5.3 versions)

What is the related PR or file link(s)?

• This PR is translated from: Clarify TiKV large-row limit in transaction restraints docs-cn#21830
• Other reference link(s): https://docs.pingcap.com/tidb/dev/dev-guide-transaction-restraints/#large-transaction-restrictions

Do your changes match any of the following descriptions?

• Delete files
• Change aliases
• Need modification after applied to another branch
• Might cause conflicts after applied to another branch

Summary by CodeRabbit

• Documentation
  • Clarified large transaction restrictions by documenting TiKV’s per-write request size limit (default 8 MiB).
  • Added guidance to adjust both TiDB’s and TiKV’s size settings when large rows cause TiKV to reject a request.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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• develop/dev-guide-transaction-restraints.md

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📝 Walkthrough

Walkthrough

The transaction restraints guide now documents TiKV’s default 8 MiB per-write-request limit and advises adjusting it together with TiDB’s transaction entry size limit for large rows.

Changes

Transaction restraints documentation

Layer / File(s)	Summary
Document combined transaction size limits develop/dev-guide-transaction-restraints.md	Adds TiKV’s raftstore.raft-entry-max-size limit and guidance to adjust it alongside tidb_txn_entry_size_limit for large rows.

Estimated code review effort: 1 (Trivial) | ~2 minutes

Possibly related PRs

• pingcap/docs#23338: Updates the same transaction restraints section with related TiKV request-size guidance.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the doc change about the TiKV large-row limit in transaction restraints.
Description check	✅ Passed	The description covers the required change, affected versions, and related links, so it mostly matches the template.
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.

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[coderabbitai]

Actionable comments posted: 1

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Configuration used: Path: .coderabbit.yaml

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Reviewing files that changed from the base of the PR and between afde45c and 90d6b86.

📒 Files selected for processing (1)

• develop/dev-guide-transaction-restraints.md

[qiancai]

/approve

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch master: #23351.
But this PR has conflicts, please resolve them!