Update the Compatibility changes of release-8.5.4 (#22233)

[ti-chi-bot]

This is an automated cherry-pick of #22233

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• This PR is translated from:Update the Compatibility changes of release-8.5.4 docs-cn#21215
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• Delete files
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[gemini-code-assist]

Summary of Changes

Hello @ti-chi-bot, 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 documentation for TiDB release 8.5.4, specifically detailing compatibility changes related to system variables and configuration parameters. The changes aim to provide users with a comprehensive understanding of default value modifications, new additions, and deprecations, ensuring a smoother upgrade experience, particularly for clusters with custom performance tuning.

Highlights

• Documentation Structure Enhancement: The compatibility changes section for TiDB 8.5.4 has been refactored to use a clear table format for both system variables and configuration parameters, improving readability and information accessibility.
• System Variable Adjustments: The default value of tidb_mpp_store_fail_ttl is now 0s, removing unnecessary delays for new TiFlash nodes. tidb_replica_read now strictly applies to read-only SQL statements, enhancing data safety. Three new system variables (tidb_opt_enable_no_decorrelate_in_select, tidb_opt_enable_semi_join_rewrite, tidb_stats_update_during_ddl) have been introduced to control query optimization and DDL-embedded ANALYZE behavior.
• Configuration Parameter Updates: TiKV's rocksdb.max-manifest-file-size default increased to 256MiB to mitigate frequent manifest file compactions. TiKV gRPC connection parameters (server.grpc-raft-conn-num, server.grpc-concurrency) now dynamically adapt to CPU core counts for optimized performance. Several legacy TiKV compaction-related parameters have been deprecated and replaced by a new gc.auto-compaction configuration group for better control over automatic compaction. A new TiFlash parameter, flash.graceful_wait_shutdown_timeout, has been added to manage the graceful shutdown process for TiFlash servers.

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[gemini-code-assist]

Code Review

This pull request updates the compatibility changes for the v8.5.4 release notes. The changes are well-structured, moving from a list to a more readable table format, and include additional details on system variables and configuration parameters. My feedback focuses on minor grammatical and stylistic improvements to enhance clarity and adhere to the documentation style guide, primarily by converting passive voice to active voice.

[hfxsd]

/approve

[ti-chi-bot]

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This pull-request has been approved by: hfxsd

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