Add maximum lifetime of connections

[sunxiaoguang]

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[gemini-code-assist]

Summary of Changes

Hello @sunxiaoguang, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request updates the TiDB Cloud serverless limitations documentation to include important information regarding database client connection lifetimes. The change aims to inform users about potential connection terminations for long-lived connections and provides a recommended starting point for connection lifetime settings to help prevent unexpected service impacts.

Highlights

• Documentation Update: Added a new limitation to the serverless-limitations.md file, specifically detailing the maximum lifetime of database client connections.
• Connection Lifetime Guidance: The documentation now advises that database client connections held open longer than 30 minutes may be terminated unexpectedly, recommending an initial 5-minute maximum connection lifetime to manage potential tail latency.

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[gemini-code-assist]

Code Review

This pull request adds an important limitation regarding the maximum lifetime of database connections for serverless clusters. My review includes a suggestion to correct a typo and rephrase the new content for better clarity and adherence to the documentation style guide, making the recommendation more direct for the user.

[ti-chi-bot]

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[sunxiaoguang]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds documentation about configuring the maximum lifetime of connections to prevent disruptions. The changes are made in dev-guide-connection-parameters.md and tidb-cloud/serverless-limitations.md.

My review focuses on improving clarity and adhering to the documentation style guide. I've suggested rephrasing some sentences to use active voice and address the user directly, which makes the content more engaging and easier to understand. I also recommended a formatting change for consistency with the rest of the document and the style guide.

Overall, the changes are good and provide valuable information for users.

[gemini-code-assist]

According to the style guide, options should be enclosed in backticks.¹ To ensure consistency throughout the document, I suggest wrapping these parameter names in backticks.

<SimpleTab>
<div label="HikariCP">

- `maxLifetime`: The maximum lifetime of a connection in the pool.

</div>

<div label="tomcat-jdbc">

- `maxAge`: The maximum lifetime of a connection in the pool.

</div>

<div label="c3p0">

- `maxConnectionAge`: The maximum lifetime of a connection in the pool.

</div>

<div label="dbcp">

- `maxConnLifetimeMillis`: The maximum lifetime of a connection in the pool.

</div>
</SimpleTab>

Style Guide References

Footnotes

1. The style guide specifies that options should be enclosed in backticks. ↩

[likidu]

LGTM