docs: clarify Raft leader lease timing

[wenxiaojie1]

What is changed, added or deleted? (Required)

Document the startup constraint for raft-store-max-leader-lease: its value must leave one raft-base-tick-interval before the Raft election timeout. This reflects the TiKV configuration validation and helps prevent invalid timing configurations from causing startup failures.

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

• This PR is translated from:
• Other reference link(s): TiKV Configuration File: The dependencies between parameters should be clearly described #20966, https://github.com/tikv/tikv/blob/master/components/raftstore/src/store/config.rs

AI agent involvement

• The changes in this PR were primarily made by an AI agent on behalf of the PR author.

Do your changes match any of the following descriptions?

• Delete files
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• Might cause conflicts after applied to another branch

Summary by CodeRabbit

• Documentation
  • Added a startup configuration constraint for raft-store-max-leader-lease.
  • TiKV will not start successfully if this value exceeds the permitted election timeout threshold.

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[gemini-code-assist]

Code Review

This pull request updates the tikv-configuration-file.md documentation to add a constraint for the raft-store-max-leader-lease configuration option. The review feedback suggests rewriting the added sentence in the second person ("you") to align with the repository style guide and removing unnecessary backticks around the numeric literal 1.

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[gemini-code-assist]

According to the repository style guide, we should write in the second person ("you") when addressing users. Additionally, the number 1 in the formula does not need to be in backticks as it is a numeric literal rather than a configuration option or command.

Suggested change

	+ To start TiKV successfully, set this value to no more than `raft-base-tick-interval` * (`raft-election-timeout-ticks` - `1`).
	+ To start TiKV successfully, you must set this value to no more than `raft-base-tick-interval` * (`raft-election-timeout-ticks` - 1).

References

1. Write in second person ("you") when addressing users. ^(link)

[qiancai]

/cc @pingyu

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2026-07-25 07:33:58.788916388 +0000 UTC m=+1649424.825011434: ☑️ agreed by qiancai.

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📥 Commits

Reviewing files that changed from the base of the PR and between 2da195b and 6b22406.

📒 Files selected for processing (1)

• tikv-configuration-file.md

📝 Walkthrough

Walkthrough

The TiKV configuration documentation adds a startup constraint for raft-store-max-leader-lease, defining its maximum value from raft-base-tick-interval and raft-election-timeout-ticks.

Changes

TiKV configuration documentation

Layer / File(s)	Summary
Document leader lease startup constraint tikv-configuration-file.md	Documents the upper bound required for raft-store-max-leader-lease for TiKV startup to succeed.

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

Suggested reviewers: qiancai, mittalrishabh

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the documentation update about Raft leader lease timing.
Description check	✅ Passed	The description includes the required change summary, affected version, related links, and AI involvement sections.
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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