[WIP]: add v8.5.5 release notes #21195

qiancai · 2025-12-16T08:12:29Z

What is changed, added or deleted? (Required)

As in the title, this PR adds the release note doc for v8.5.5.

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This PR is translated from: [WIP]: add v8.5.5 release notes docs#22190
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ti-chi-bot · 2025-12-17T06:13:02Z

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releases/release-8.5.5.md

Co-authored-by: zhaoshangzi <[email protected]> Co-authored-by: Frank945946 <[email protected]>

joechenrh

LGTM, for the ADD INDEX part.

ti-chi-bot · 2025-12-23T09:47:11Z

@joechenrh: adding LGTM is restricted to approvers and reviewers in OWNERS files.

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In response to this:

LGTM

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qiancai · 2025-12-24T06:47:59Z

releases/release-8.5.5.md

+
+    更多信息，请参考[用户文档](链接)。
+
+* 按时间点恢复 (Point-in-time recovery, PITR) 支持从压缩后的日志备份中恢复，以加快恢复速度 [#56522](https://github.com/pingcap/tidb/issues/56522) @[YuJuncen](https://github.com/YuJuncen) **tw@lilin90** <!--2001-->


这条的中文目前是从 v9.0.0 复制过来的之前的描述，麻烦请按照 https://github.com/pingcap/docs/pull/22190/files 里最新的英文进行调整 @lilin90

qiancai · 2025-12-24T06:48:14Z

releases/release-8.5.5.md

+
+    更多信息，请参考[用户文档](https://docs.pingcap.com/zh/tidb/v8.5/tikv-configuration-file#graceful-shutdown-timeout-从-v855-版本开始引入)。
+
+* 提升进行中的日志备份与快照恢复的兼容性 [#58685](https://github.com/pingcap/tidb/issues/58685) @[BornChanger](https://github.com/BornChanger) **tw@lilin90** <!--2000-->


这条的中文目前是从 v9.0.0 复制过来的之前的描述，麻烦请按照 https://github.com/pingcap/docs/pull/22190/files 里最新的英文进行调整 @lilin90

Co-authored-by: zhaoshangzi <[email protected]>

releases/release-8.5.5.md

lcwangchao · 2025-12-25T02:43:24Z

releases/release-8.5.5.md

+
+* 提示索引下推到TiKV提升查询性能 [#62575](https://github.com/pingcap/tidb/issues/62575) @[lcwangchao](https://github.com/lcwangchao) **tw@qiancai** <!--1899-->
+
+    通过hint INDEX_LOOKUP_PUSHDOWN(t1_name, idx1_name [, idx2_name ...]) 提示优化器将指定索引查询下推到TiKV，减少远程调用的次数，经过测试数据对比显示性能可提升约20%左右，最优可提升到40%。本特性一般建议结合表 affinity 属性使用，即表属性 AFFINITY="table" 或者 分区表属性 AFFINITY="partition" 。


实际数据可能根据环境和负载不同有很大区别，这个数据目前是混合负载的结果，不光包含 pushdown

@zhaoshangzi PTAL

通过hint INDEX_LOOKUP_PUSHDOWN(t1_name, idx1_name [, idx2_name ...]) 提示优化器将指定索引查询下推到TiKV，减少远程调用的次数，性能在理论上有提升，但具体提升比例需要结合业务场景实际测试。本特性一般建议结合表 affinity 属性使用，即表属性 AFFINITY="table" 或者分区表属性 AFFINITY="partition" 。

qiancai · 2026-01-07T08:03:56Z

releases/release-8.5.5.md

+| -------- | -------- | -------- | -------- |
+| PD | [`schedule.max-affinity-merge-region-size`](https://docs.pingcap.com/zh/tidb/v8.5/pd-configuration-file#max-affinity-merge-region-size-从-v855-版本开始引入) | 新增 | 控制属于同一[亲和性](https://docs.pingcap.com/zh/tidb/v8.5/table-affinity)分组中相邻的小 Region 自动合并的阈值，默认值为 `256`，单位为 MiB。 |
+| PD  | [`schedule.affinity-schedule-limit`](https://docs.pingcap.com/zh/tidb/v8.5/pd-configuration-file#affinity-schedule-limit-从-v855-版本开始引入) | 新增 | 控制同时进行的[亲和性](https://docs.pingcap.com/zh/tidb/v8.5/table-affinity)调度任务数量，默认值为 `0`，表示亲和性调度默认关闭。 |
+| TiKV | [`performance.enable-async-batch-get`](https://docs.pingcap.com/zh/tidb/v8.5/tikv-configuration-file#enable-async-batch-get-从-v855-版本开始引入)  | 新增 | 控制 TiDB 是否使用异步方式执行 Batch Get 算子，默认值为 `true`。 |


Suggested change

| TiKV | [`performance.enable-async-batch-get`](https://docs.pingcap.com/zh/tidb/v8.5/tikv-configuration-file#enable-async-batch-get-从-v855-版本开始引入) | 新增 | 控制 TiDB 是否使用异步方式执行 Batch Get 算子，默认值为 `true`。 |

| TiDB | [`performance.enable-async-batch-get`](https://docs.pingcap.com/zh/tidb/v8.5/tidb-configuration-file#enable-async-batch-get-从-v855-版本开始引入) | 新增 | 控制 TiDB 是否使用异步方式执行 Batch Get 算子，默认值为 `true`。 |

releases/release-8.5.5.md

hfxsd · 2026-01-08T02:30:47Z

releases/release-8.5.5.md

+    - fix incorrect initialization for foreign key related fields when copying table info [#61668](https://github.com/pingcap/tidb/issues/61668) @[tangenta](https://github.com/tangenta)
+    - 修复多个 schema 变更时，内嵌于 DDL 的 Analyze 特性可能不会启用的问题 [#65040](https://github.com/pingcap/tidb/issues/65040) @[joechenrh](https://github.com/joechenrh)
+    - 修复取消 ADD INDEX 任务后，分布式执行框架 (Distributed eXecution Framework, DXF) 任务没有取消的问题 [#issue](https://github.com/pingcap/tidb/issues/64129) @[tangenta](https://github.com/tangenta)
+    - fix incorrect check to determing whether to load table info for tables contain foreign key [#60444](https://github.com/pingcap/tidb/issues/60444) @[JQWong7](https://github.com/JQWong7)


@joechenrh PTAL

hfxsd · 2026-01-08T02:31:54Z

releases/release-8.5.5.md

+    - 修复在升级时 TiDB 节点可能会卡住的问题 [#64539](https://github.com/pingcap/tidb/issues/64539) @[joechenrh](https://github.com/joechenrh)
+    - 修复当没有索引数据时，admin check 没有报错的问题 [#issue](https://github.com/pingcap/tidb/issues/63698) @[wjhuang2016](https://github.com/wjhuang2016)
+    - 修复执行 `MODIFY COLUMN` 修改排序规则时，数据索引不一致的问题 [#61668](https://github.com/pingcap/tidb/issues/61668) @[tangenta](https://github.com/tangenta)
+    - fix incorrect initialization for foreign key related fields when copying table info [#61668](https://github.com/pingcap/tidb/issues/61668) @[tangenta](https://github.com/tangenta)


@joechenrh PTAL

hfxsd · 2026-01-08T02:39:52Z

releases/release-8.5.5.md

+    - 修复缓存表在走 TiFlash 副本读取时可能出现的 goroutine 和内存泄漏问题 [#63329](https://github.com/pingcap/tidb/issues/63329) @[xzhangxian1008](https://github.com/xzhangxian1008)
+    - 修复执行 `ALTER TABLE child CHANGE COLUMN` 修改列后，外键 (Foreign Key) 没有更新的问题 [#59705](https://github.com/pingcap/tidb/issues/59705) @[fzzf678](https://github.com/fzzf678) <!--tw@hfxsd: the following 16 notes--> 
+    - 修复解码旧版本 TiDB 的 `RENAME TABLE` 任务 arg 时出现错误的问题 [#64413](https://github.com/pingcap/tidb/issues/64413) @[joechenrh](https://github.com/joechenrh)
+    - fix missing rebase auto increment not executed if BR restore failed [#64761](https://github.com/pingcap/tidb/issues/64761) @[joechenrh](https://github.com/joechenrh)


@joechenrh PTAL

releases/release-8.5.5.md

joechenrh · 2026-01-08T02:49:28Z

releases/release-8.5.5.md

+
+### SQL 功能
+
+* 支持在线修改分布式 `ADD INDEX` 任务的并发和吞吐 [#62120](https://github.com/pingcap/tidb/pull/62120) @[joechenrh](https://github.com/joechenrh) **tw@qiancai** <!--2326-->


Suggested change

* 支持在线修改分布式 `ADD INDEX` 任务的并发和吞吐 [#62120](https://github.com/pingcap/tidb/pull/62120) @[joechenrh](https://github.com/joechenrh) **tw@qiancai** 

* 支持在线修改分布式 `ADD INDEX` 任务的并发和吞吐 [#64947](https://github.com/pingcap/tidb/issues/64947) @[joechenrh](https://github.com/joechenrh) **tw@qiancai**

releases/release-8.5.5.md

Co-authored-by: Ruihao Chen <[email protected]>

releases/release-8.5.5.md

qiancai · 2026-01-08T09:05:33Z

releases/release-8.5.5.md

+
+    + TiCDC <!--tw@qiancai: 1 note-->
+
+        - 为创建 changefeed 增加更全面的检查 [#12253](https://github.com/pingcap/tiflow/issues/12253) @[wk989898](https://github.com/wk989898)


Suggested change

- 为创建 changefeed 增加更全面的检查 [#12253](https://github.com/pingcap/tiflow/issues/12253) @[wk989898](https://github.com/wk989898)

- 增强 Changefeed 的配置检查逻辑，在创建或更新 Changefeed 时，若 Dispatcher 配置引用的列不存在，将直接报错并拒绝操作，避免任务运行失败 [#12253](https://github.com/pingcap/tiflow/issues/12253) @[wk989898](https://github.com/wk989898)

releases/release-8.5.5.md

qiancai · 2026-01-08T09:33:30Z

releases/release-8.5.5.md

+        - 修复同步到存储类型下游时可能因为 writer close 操作失败而导致的数据丢失问题 [#12436](https://github.com/pingcap/tiflow/issues/12436) @[wk989898](https://github.com/wk989898)
+        - 修复同步 truncate partition 操作可能导致 changefeed 失败的问题 [#12430](https://github.com/pingcap/tiflow/issues/12430) @[wk989898](https://github.com/wk989898)
+        - 修复同步多表 DDL语句时产生的不正确的 DDL 执行顺序 [#12449](https://github.com/pingcap/tiflow/issues/12449) @[wlwilliamx](https://github.com/wlwilliamx)
+        - 升级 aws-sdk-go-v2 依赖以修复 glue schema 的注册问题[#12424](https://github.com/pingcap/tiflow/issues/12424) @[wk989898](https://github.com/wk989898)
+        - 修复引起 memory quota 无法正常释放的问题[#18169](https://github.com/tikv/tikv/issues/18169) @[asddongmen](https://github.com/asddongmen)
+        - 修复引起 memory quota 无法正常释放的问题[#18915](https://github.com/tikv/tikv/issues/18915) @[asddongmen](https://github.com/asddongmen)


Suggested change

- 修复同步到存储类型下游时可能因为 writer close 操作失败而导致的数据丢失问题 [#12436](https://github.com/pingcap/tiflow/issues/12436) @[wk989898](https://github.com/wk989898)

- 修复同步 truncate partition 操作可能导致 changefeed 失败的问题 [#12430](https://github.com/pingcap/tiflow/issues/12430) @[wk989898](https://github.com/wk989898)

- 修复同步多表 DDL语句时产生的不正确的 DDL 执行顺序 [#12449](https://github.com/pingcap/tiflow/issues/12449) @[wlwilliamx](https://github.com/wlwilliamx)

- 升级 aws-sdk-go-v2 依赖以修复 glue schema 的注册问题[#12424](https://github.com/pingcap/tiflow/issues/12424) @[wk989898](https://github.com/wk989898)

- 修复引起 memory quota 无法正常释放的问题[#18169](https://github.com/tikv/tikv/issues/18169) @[asddongmen](https://github.com/asddongmen)

- 修复引起 memory quota 无法正常释放的问题[#18915](https://github.com/tikv/tikv/issues/18915) @[asddongmen](https://github.com/asddongmen)

- 修复同步数据到对象存储（Storage Sink）时，可能因未正确捕获 Writer 关闭错误而导致数据丢失的问题 [#12436](https://github.com/pingcap/tiflow/issues/12436) @[wk989898](https://github.com/wk989898)

- 修复同步分区表的 `TRUNCATE` 操作可能导致 Changefeed 失败的问题 [#12430](https://github.com/pingcap/tiflow/issues/12430) @[wk989898](https://github.com/wk989898)

- 修复同步多表重命名 DDL 时，下游执行顺序可能不正确的问题 [#12449](https://github.com/pingcap/tiflow/issues/12449) @[wlwilliamx](https://github.com/wlwilliamx)

- 升级 `aws-sdk-go-v2` 依赖版本，以修复使用 Glue Schema Registry 时可能遇到的连接错误 [#12424](https://github.com/pingcap/tiflow/issues/12424) @[wk989898](https://github.com/wk989898)

- 修复 TiKV CDC 组件重启后可能无法正确释放内存配额，导致 Changefeed 任务卡住的问题 [#18169](https://github.com/tikv/tikv/issues/18169) @[asddongmen](https://github.com/asddongmen)

- 修复 TiKV CDC 在增量扫描任务堆积时，gRPC 连接可能因误判为空闲而被异常断开的问题 [#18915](https://github.com/tikv/tikv/issues/18915) @[asddongmen](https://github.com/asddongmen)

@hongyunyan PTAL

ti-chi-bot · 2026-01-08T10:06:05Z

@qiancai: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-verify	`f4397a7`	link	true	`/test pull-verify`

Full PR test history. Your PR dashboard.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.

Add temp.md

813850f

qiancai added do-not-merge/work-in-progress Indicates that a PR should not merge because it is a work in progress. needs-cherry-pick-release-8.5 Should cherry pick this PR to release-8.5 branch. translation/from-docs This PR is translated from a PR in pingcap/docs. labels Dec 16, 2025

Delete temp.md

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ti-chi-bot bot added the size/XS Denotes a PR that changes 0-9 lines, ignoring generated files. label Dec 16, 2025

Create release-8.5.5.md

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ti-chi-bot bot added size/L Denotes a PR that changes 100-499 lines, ignoring generated files. and removed size/XS Denotes a PR that changes 0-9 lines, ignoring generated files. labels Dec 16, 2025

qiancai self-assigned this Dec 16, 2025

add feature description for #56522 and #58685

42a91b0

add pingcap#17221

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Frank945946 reviewed Dec 22, 2025

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zhaoshangzi reviewed Dec 23, 2025

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Add three features

a5f361c

Co-authored-by: zhaoshangzi <[email protected]> Co-authored-by: Frank945946 <[email protected]>

joechenrh approved these changes Dec 23, 2025

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add more features according to English PR

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qiancai commented Dec 24, 2025

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add improvements and bug fixes

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qiancai and others added 2 commits December 25, 2025 09:55

add two new features

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Co-authored-by: zhaoshangzi <[email protected]>

adjust the feature order and add two features

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qiancai commented Dec 25, 2025

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