diff --git a/markdown-pages/en/tidb/release-7.6/releases/release-7.6.0.md b/markdown-pages/en/tidb/release-7.6/releases/release-7.6.0.md index f13bc62..cc8bb26 100644 --- a/markdown-pages/en/tidb/release-7.6/releases/release-7.6.0.md +++ b/markdown-pages/en/tidb/release-7.6/releases/release-7.6.0.md @@ -116,15 +116,6 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with- For more information, see [documentation](/ddl-v2.md). -* The optimizer enhances support for multi-valued indexes [#47759](https://github.com/pingcap/tidb/issues/47759) [#46539](https://github.com/pingcap/tidb/issues/46539) @[Arenatlx](https://github.com/Arenatlx) @[time-and-fate](https://github.com/time-and-fate) **tw@ran-huang** - - Starting from v6.6.0, TiDB introduced [multi-value indexes](/sql-statements/sql-statement-create-index.md#multi-valued-indexes) to improve query performance for JSON data types. In v7.6.0, the optimizer enhances its support for multi-valued indexes and can correctly identify and utilize them to optimize queries in complex scenarios. - - * Statistics on multi-valued indexes are collected and applied by the optimizer for estimation. When a SQL statement might select multiple multi-valued indexes, the optimizer can identify the index with lower cost. - * When there are multiple `member of` conditions connected by `OR`, the optimizer is able to match an effective index partial path for each DNF item (a `member of` condition) and combine multiple paths using Union to form an `Index Merge`. This allows more efficient condition filtering and data querying. - - For more information, see [documentation](/sql-statements/sql-statement-create-index.md#multi-valued-indexes). - * Support periodic full compaction (experimental) [#12729](https://github.com/tikv/tikv/issues/12729) **tw@Oreoxmt** Starting from v7.6.0, TiDB supports periodic full compaction for TiKV. This feature serves as enhancement to Garbage Collection (GC) to eliminate redundant data versions. In scenarios where application activity shows obvious peaks and valleys, you can use this feature to perform data compaction during idle periods to improve the performance during peak periods. @@ -170,7 +161,7 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with- * `LOAD DATA` supports explicit transactions and rollbacks [#49079](https://github.com/pingcap/tidb/pull/49079) @[ekexium](https://github.com/ekexium) **tw@Oreoxmt** - Compared with MySQL, the transactional behavior of the`LOAD DATA` statement varies in different TiDB versions before v7.6.0, so you might need to make additional adjustments when using this statement. Specifically, before v4.0.0, `LOAD DATA` commits every 20000 rows. From v4.0.0 to v6.6.0, TiDB commits all rows in one transaction by default and also supports committing every fixed number of rows by setting the [`tidb_dml_batch_size`](/system-variables.md#tidb_dml_batch_size) system variable. Starting from v7.0.0, `tidb_dml_batch_size` no longer takes effect on `LOAD DATA` and TiDB commits all rows in one transaction. + Compared with MySQL, the transactional behavior of the `LOAD DATA` statement varies in different TiDB versions before v7.6.0, so you might need to make additional adjustments when using this statement. Specifically, before v4.0.0, `LOAD DATA` commits every 20000 rows. From v4.0.0 to v6.6.0, TiDB commits all rows in one transaction by default and also supports committing every fixed number of rows by setting the [`tidb_dml_batch_size`](/system-variables.md#tidb_dml_batch_size) system variable. Starting from v7.0.0, `tidb_dml_batch_size` no longer takes effect on `LOAD DATA` and TiDB commits all rows in one transaction. Starting from v7.6.0, TiDB processes `LOAD DATA` in transactions in the same way as other DML statements, especially in the same way as MySQL. The `LOAD DATA` statement in a transaction no longer automatically commits the current transaction or starts a new transaction. Moreover, you can explicitly commit or roll back the `LOAD DATA` statement in a transaction. Additionally, the `LOAD DATA` statement is affected by the TiDB transaction mode setting (optimistic or pessimistic transaction). These improvements simplify the migration process from MySQL to TiDB and offer a more unified and controllable experience for data import. @@ -226,11 +217,11 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with- As more and more users use resource groups to isolate application workloads, Resource Control provides enhanced data based on resource groups. This helps you monitor resource group workloads and settings, ensuring that you can quickly identify and accurately diagnose problems, including: - * [Slow Queries](/identify-slow-queries.md): add the resource group name, RU consumption, and time for waiting for resources. + * [Slow Queries](/identify-slow-queries.md): add the resource group name, resource unit (RU) consumption, and time for waiting for resources. * [Statement Summary Tables](/statement-summary-tables.md): add the resource group name, RU consumption, and time for waiting for resources. * In the system variable [`tidb_last_query_info`](/system-variables.md#tidb_last_query_info-new-in-v4014), add a new entry `ru_consumption` to indicate the consumed [RU](/tidb-resource-control.md#what-is-request-unit-ru) by SQL statements. You can use this variable to get the resource consumption of the last statement in the session. * Add database metrics based on resource groups: QPS/TPS, execution time (P999/P99/P95), number of failures, number of connections. - * Add the system table [`request_unit_by_group`](/mysql-schema.md#system-tables-related-to-resource-control) to record the history records of daily consumed resource units (RUs) of all resource groups. + * Add the system table [`request_unit_by_group`](/mysql-schema.md#system-tables-related-to-resource-control) to record the history records of daily consumed RUs of all resource groups. For more information, see [Identify Slow Queries](/identify-slow-queries.md), [Statement Summary Tables](/statement-summary-tables.md), and [Key Monitoring Metrics of Resource Control](/grafana-resource-control-dashboard.md). @@ -256,7 +247,7 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with- * TiCDC adds support for three-character delimiters with CSV output protocol [#9969](https://github.com/pingcap/tiflow/issues/9969) @[zhangjinpeng1987](https://github.com/zhangjinpeng1987) **tw@hfxsd** - Starting from v7.6.0, you can specify the CSV output protocol delimiters as 1 to 3 characters long. With this change, you can configure TiCDC to generate file output using two character delimiters (such as `||` or `$^`) or three character delimiters (such as `|@|`) to separate fields in the output. + Starting from v7.6.0, you can specify the CSV output protocol delimiters as 1 to 3 characters long. With this change, you can configure TiCDC to generate file output using two-character delimiters (such as `||` or `$^`) or three-character delimiters (such as `|@|`) to separate fields in the output. For more information, see [documentation](/ticdc/ticdc-csv.md). @@ -278,7 +269,7 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with- | [`tidb_ddl_version`](/system-variables.md#tidb_ddl_version-new-in-v760) | Newly added | Controls whether to enable [TiDB DDL V2](/ddl-v2.md). Set the value to `2` to enable it and `1` to disable it. The default value is `1`. When TiDB DDL V2 is enabled, DDL statements will be executed using TiDB DDL V2. The execution speed of DDL statements for creating tables is increased by 10 times compared with TiDB DDL V1. | | [`tidb_enable_global_index`](/system-variables.md#tidb_enable_global_index-new-in-v760) | Newly added | Controls whether to support creating `Global indexes` for partitioned tables. The default value is `OFF`. `Global index` is currently in the development stage. **It is not recommended to modify the value of this system variable**. | | [`tidb_idle_transaction_timeout`](/system-variables.md#tidb_idle_transaction_timeout-new-in-v760) | Newly added | Controls the idle timeout for transactions in a user session. When a user session is in a transactional state and remains idle for a duration exceeding the value of this variable, TiDB will terminate the session. The default value `0` means unlimited. | -| [`tidb_opt_enable_fuzzy_binding`](/system-variables.md#tidb_opt_enable_fuzzy_binding-new-in-v760) | Newly added | Controls whether to enable the cross-database binding feature. The default value `OFF` means cross-database binding is disabled by default. | +| [`tidb_opt_enable_fuzzy_binding`](/system-variables.md#tidb_opt_enable_fuzzy_binding-new-in-v760) | Newly added | Controls whether to enable the cross-database binding feature. The default value `OFF` means cross-database binding is disabled. | | [`tidb_txn_entry_size_limit`](/system-variables.md#tidb_txn_entry_size_limit-new-in-v760) | Newly added | Dynamically modifies the TiDB configuration item [`performance.txn-entry-size-limit`](/tidb-configuration-file.md#txn-entry-size-limit-new-in-v50). It limits the size of a single row of data in TiDB. The default value of this variable is `0`, which means that TiDB uses the value of the configuration item `txn-entry-size-limit` by default. When this variable is set to a non-zero value, `txn-entry-size-limit` is also set to the same value. | | [`pd_enable_follower_handle_region`](/system-variables.md#pd_enable_follower_handle_region-new-in-v760) | Newly added | Controls whether to enable the [Active PD Follower](/tune-region-performance.md#use-the-active-pd-follower-feature-to-enhance-the-scalability-of-pds-region-information-query-service) feature (experimental). When the value is `OFF`, TiDB only obtains Region information from the PD leader. When the value is `ON`, TiDB evenly distributes requests for Region information to all PD servers, and PD followers can also handle Region requests, thereby reducing the CPU pressure on the PD leader. | @@ -288,18 +279,19 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with- | -------- | -------- | -------- | -------- | | TiDB | [`tls-version`](/tidb-configuration-file.md#tls-version) | Modified | The default value is "". The default supported TLS versions of TiDB are changed from `TLS1.1` or higher to `TLS1.2` or higher. | | TiKV | [`blob-file-compression`](/tikv-configuration-file.md#blob-file-compression) | Modified | The algorithm used for compressing values in Titan, which takes value as the unit. Starting from TiDB v7.6.0, the default compression algorithm is `zstd`. | -| TiKV | [`rocksdb.defaultcf.titan.min-blob-size`](/tikv-configuration-file.md#min-blob-size) | Modified | Starting with TiDB v7.6.0, the default value for new clusters is `32KB`. For existing clusters upgrading to v7.6.0, the default value `1KB` remains unchanged. | +| TiKV | [`rocksdb.defaultcf.titan.min-blob-size`](/tikv-configuration-file.md#min-blob-size) | Modified | Starting from TiDB v7.6.0, the default value for new clusters is `32KB`. For existing clusters upgrading to v7.6.0, the default value `1KB` remains unchanged. | | TiKV | [`rocksdb.titan.enabled`](/tikv-configuration-file.md#enabled) | Modified | Enables or disables Titan. For v7.5.0 and earlier versions, the default value is `false`. Starting from v7.6.0, the default value is `true` for only new clusters. Existing clusters upgraded to v7.6.0 or later versions will retain the original configuration. | | TiDB Lightning| [`tidb.pd-addr`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-task) | Modified | Configures the addresses of the PD Servers. Starting from v7.6.0, TiDB supports setting multiple PD addresses. | -| TiDB Lightning | [`block-size`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-task) | Newly added | Controls the I/O block size for sorting local files in the physical import (`backend='local'`). The default value is `16KiB`. When the disk IOPS is a bottleneck, you can increase this value to improve performance. | -| TiKV | [`raftstore.periodic-full-compact-start-times`](/tikv-configuration-file.md#periodic-full-compact-start-times-new-in-v760) | Newly added | Sets the specific times that TiKV initiates periodic full compaction. The default value `[]` means periodic full compaction is disabled by default. | +| TiDB Lightning | [`block-size`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-task) | Newly added | Controls the I/O block size for sorting local files in Physical Import Mode (`backend='local'`). The default value is `16KiB`. When the disk IOPS is a bottleneck, you can increase this value to improve performance. | +| TiKV | [`gc.num-threads`](/tikv-configuration-file.md#num-threads-new-in-v760) | Newly added | When `enable-compaction-filter` is set to `false`, this parameter controls the number of GC threads. The default value is `1`. | +| TiKV | [`raftstore.periodic-full-compact-start-times`](/tikv-configuration-file.md#periodic-full-compact-start-times-new-in-v760) | Newly added | Sets the specific times that TiKV initiates periodic full compaction. The default value `[]` means periodic full compaction is disabled. | | TiKV | [`raftstore.periodic-full-compact-start-max-cpu`](/tikv-configuration-file.md#periodic-full-compact-start-max-cpu-new-in-v760) | Newly added | Limits the maximum CPU usage rate for TiKV periodic full compaction. The default value is `0.1`. | | TiKV | [`zstd-dict-size`](/tikv-configuration-file.md#zstd-dict-size) | Newly added | Specifies the `zstd` dictionary compression size. The default value is `"0KB"`, which means to disable the `zstd` dictionary compression. | | BR | `--granularity` | Newly added | Uses the coarse-grained Region scatter algorithm (experimental) by specifying `--granularity="coarse-grained"`. This accelerates restore speed in large-scale Region scenarios. | | BR | `--tikv-max-restore-concurrency` | Newly added | Controls the concurrency of download tasks for each TiKV node when using the coarse-grained Region scatter algorithm. | -| TiCDC | [`encoding-worker-num`](/ticdc/ticdc-changefeed-config.md) | Newly added | Controls the number of encoding and decoding workers in the redo module. The default value is 16. | -| TiCDC | [`flush-worker-num`](/ticdc/ticdc-changefeed-config.md) | Newly added | Controls the number of flushing workers in the redo module. The default value is 8. | | TiCDC | [`compression`](/ticdc/ticdc-changefeed-config.md) | Newly added | Controls the behavior to compress redo log files. | +| TiCDC | [`encoding-worker-num`](/ticdc/ticdc-changefeed-config.md) | Newly added | Controls the number of encoding and decoding workers in the redo module. The default value is `16`. | +| TiCDC | [`flush-worker-num`](/ticdc/ticdc-changefeed-config.md) | Newly added | Controls the number of flushing workers in the redo module. The default value is `8`. | | TiCDC | [`sink.cloud-storage-config`](/ticdc/ticdc-changefeed-config.md) | Newly added | Sets the automatic cleanup of historical data when replicating data to object storage. | ### System tables @@ -411,7 +403,7 @@ Starting from v7.6.0, the `TiDB-community-server` [binary-package](/binary-packa - Fix the issue that invalid `EXTRA` column type in `INFORMATION_SCHEMA.COLUMNS` leads to the error `Data Too Long, field len 30, data len 45` [#42030](https://github.com/pingcap/tidb/issues/42030) @[tangenta](https://github.com/tangenta) - Fix the issue that `IN (...) ` causes different plan digests in `INFORMATION_SCHEMA.STATEMENTS_SUMMARY` [#33559](https://github.com/pingcap/tidb/issues/33559) @[King-Dylan](https://github.com/King-Dylan) - Fix the issue that when converting the `TIME` type to the `YEAR` type, the returned result mixes `TIME` and the year [#48557](https://github.com/pingcap/tidb/issues/48557) @[YangKeao](https://github.com/YangKeao) - - Fix the issue that disabling `tidb_enable_collect_execution_info` causes the coppercessor cache to panic [#48212](https://github.com/pingcap/tidb/issues/48212) @[you06](https://github.com/you06) + - Fix the issue that disabling `tidb_enable_collect_execution_info` causes the coprocessor cache to panic [#48212](https://github.com/pingcap/tidb/issues/48212) @[you06](https://github.com/you06) - Fix the issue that TiDB crashes when `shuffleExec` quits unexpectedly [#48230](https://github.com/pingcap/tidb/issues/48230) @[wshwsh12](https://github.com/wshwsh12) - Fix the issue that static `CALIBRATE RESOURCE` relies on the Prometheus data [#49174](https://github.com/pingcap/tidb/issues/49174) @[glorv](https://github.com/glorv) - Fix the issue that when adding a large interval to a date, it returns an incorrect result. After the fix, an interval with an invalid prefix or the string `true` is treated as zero, which is consistent with MySQL 8.0 [#49227](https://github.com/pingcap/tidb/issues/49227) @[lcwangchao](https://github.com/lcwangchao) diff --git a/markdown-pages/zh/tidb/release-7.6/releases/release-7.6.0.md b/markdown-pages/zh/tidb/release-7.6/releases/release-7.6.0.md index 719cf54..7d2d9c6 100644 --- a/markdown-pages/zh/tidb/release-7.6/releases/release-7.6.0.md +++ b/markdown-pages/zh/tidb/release-7.6/releases/release-7.6.0.md @@ -112,19 +112,10 @@ TiDB 版本：7.6.0 * 建表性能提升 10 倍（实验特性）[#49752](https://github.com/pingcap/tidb/issues/49752) @[gmhdbjd](https://github.com/gmhdbjd) **tw@hfxsd** - 在之前的版本里，将上游数据库上万张表迁移到 TiDB 时，TiDB 创建这些表耗时长，效率低。从 v7.6.0 开始，引入了新的 TiDB DDL V2 架构，你可以通过设置系统变量 [`tidb_ddl_version`](/system-variables.md#tidb_ddl_version-从-v760-版本开始引入) 开启。相比之前的版本，新版本的 DDL 批量建表性能实现了高达 10 倍的提升，大幅减少了建表时间。 + 在之前的版本里，将上游数据库上万张表迁移到 TiDB 时，TiDB 创建这些表耗时长，效率低。从 v7.6.0 开始，引入了新的 TiDB DDL V2 架构，你可以通过设置系统变量 [`tidb_ddl_version`](/system-variables.md#tidb_ddl_version-从-v760-版本开始引入) 开启。相比之前的版本，新版本的 DDL 批量建表性能提升了高达 10 倍，从而大幅减少了建表时间。 更多信息，请参考[用户文档](/ddl-v2.md)。 -* 优化器增强对多值索引的支持 [#47759](https://github.com/pingcap/tidb/issues/47759) [#46539](https://github.com/pingcap/tidb/issues/46539) @[Arenatlx](https://github.com/Arenatlx) @[time-and-fate](https://github.com/time-and-fate) **tw@ran-huang** - - TiDB 自 v6.6.0 开始引入[多值索引](/sql-statements/sql-statement-create-index.md#多值索引)，提升对 JSON 数据类型的检索性能。在 v7.6.0 中，优化器增强了对多值索引的支持能力，在复杂使用场景下，能够正确识别和利用多值索引来优化查询。 - - * 多值索引上的统计信息会被收集，并应用于优化器估算。当一条 SQL 可能选择到数个多值索引时，优化器可以识别开销更小的索引。 - * 当出现用 `OR` 连接的多个 `member of` 条件时，优化器能够为每个 DNF Item（`member of` 条件）匹配一个有效的 Index Partial Path 路径，并将多条路径以 Union 的方式综合起来组成 `Index Merge` 来做更高效的条件过滤和数据读取。 - - 更多信息，请参考[用户文档](/sql-statements/sql-statement-create-index.md#多值索引)。 - * 支持周期性全量数据整理（实验特性）[#12729](https://github.com/tikv/tikv/issues/12729) **tw@Oreoxmt** 从 v7.6.0 开始，TiDB 支持 TiKV 周期性全量数据整理。该功能可以作为垃圾回收 (GC) 的增强，用以消除冗余的数据版本。在业务活动呈现明显的高峰和低谷的场景中，利用该功能可在系统空闲时段进行数据整理，以提升高峰期间业务处理的性能。 @@ -254,7 +245,7 @@ TiDB 版本：7.6.0 更多信息，请参考[用户文档](/ticdc/ticdc-open-api-v2.md#查询特定同步任务是否完成)。 -* TiCDC 增加支持将 CSV 格式中的 delimiter 设置为 3 个字符 [#9969](https://github.com/pingcap/tiflow/issues/9969) @[zhangjinpeng1987](https://github.com/zhangjinpeng1987) **tw@hfxsd** +* TiCDC 支持将 CSV 格式中的 delimiter 设置为 3 个字符 [#9969](https://github.com/pingcap/tiflow/issues/9969) @[zhangjinpeng1987](https://github.com/zhangjinpeng1987) **tw@hfxsd** 从 v7.6.0 开始，你可以将 TiCDC 输出的 CSV 格式中的 delimiter 设置为 1 到 3 个字符。例如，你可以指定 TiCDC 使用 2 个字符的 delimiter （例如 `||` 或 `$^`）或 3 个字符的 delimiter（例如 `|@|`）分隔字段。 @@ -274,7 +265,7 @@ TiDB 版本：7.6.0 ### MySQL 兼容性 -* 兼容性 1 +* 在 TiDB v7.6.0 版本之前，`LOAD DATA` 操作在一个事务中提交所有行，或者以批量方式提交事务，和 MySQL 的行为略有不同。从 TiDB v7.6.0 版本开始，`LOAD DATA` 的事务行为与 MySQL 的事务行为一致，包括事务内的 `LOAD DATA` 语句本身不再自动提交当前事务，也不会开启新事务，并且事务内的 `LOAD DATA` 语句可以被显式提交或者回滚。此外，`LOAD DATA` 语句会受 TiDB 事务模式设置（乐观/悲观）影响。 * 兼容性 2 @@ -288,7 +279,7 @@ TiDB 版本：7.6.0 | [`tidb_ddl_version`](/system-variables.md#tidb_ddl_version-从-v760-版本开始引入) | 新增 | 用于控制是否开启 [TiDB DDL V2](/ddl-v2.md)。将该变量的值设置为 `2` 可以开启该功能，设置为 `1` 关闭该功能。默认值为 `1`。开启后，将使用新版本的实现执行 DDL 语句。TiDB DDL V2 对 DDL 功能做了提升，建表 DDL 的执行速度相比 V1 版本提升 10 倍。 | | [`tidb_enable_global_index`](/system-variables.md#tidb_enable_global_index-从-v760-版本开始引入) | 新增 | 用于控制是否支持对分区表创建 `Global index`。默认值为 `OFF`。`Global index` 当前正处于开发阶段，**不推荐修改该变量值**。 | | [`tidb_idle_transaction_timeout`](/system-variables.md#tidb_idle_transaction_timeout-从-v760-版本开始引入) | 新增 | 用来控制用户会话中事务的空闲超时。当用户会话处于事务状态且空闲时间超过该变量设定的值时，会话会被 Kill 掉。默认值 `0` 表示没有时间限制。 | -| [`tidb_opt_enable_fuzzy_binding`](/system-variables.md#tidb_opt_enable_fuzzy_binding-从-v760-版本开始引入) | 新增 | 用于控制是否开启跨数据库绑定执行计划功能，默认值 `OFF` 表示默认关闭。 | +| [`tidb_opt_enable_fuzzy_binding`](/system-variables.md#tidb_opt_enable_fuzzy_binding-从-v760-版本开始引入) | 新增 | 用于控制是否开启跨数据库绑定执行计划功能，默认值 `OFF` 表示关闭。 | | [`tidb_txn_entry_size_limit`](/system-variables.md#tidb_txn_entry_size_limit-从-v760-版本开始引入) | 新增 | 用于动态修改 TiDB 配置项 [`performance.txn-entry-size-limit`](/tidb-configuration-file.md#txn-entry-size-limit-从-v50-版本开始引入)，即限制 TiDB 单行数据的大小。默认值为 `0`，表示默认使用配置项的值。当设置为非 `0` 值时，优先使用该变量的值作为 `txn-entry-size-limit` 的值。 | | [`pd_enable_follower_handle_region`](/system-variables.md#pd_enable_follower_handle_region-从-v760-版本开始引入) | 新增 | 用于控制是否开启 [Active PD Follower](/tune-region-performance.md#通过-active-pd-follower-提升-pd-region-信息查询服务的扩展能力)（实验特性）。当该值为 `OFF` 时，TiDB 仅从 PD leader 获取 Region 信息。当该值为 `ON` 时，TiDB 在获取 Region 信息时会将请求均匀地发送到所有 PD 节点上，因此 PD follower 也可以处理 Region 信息请求，从而减轻 PD leader 的 CPU 压力。 | @@ -297,19 +288,20 @@ TiDB 版本：7.6.0 | 配置文件 | 配置项 | 修改类型 | 描述 | | -------- | -------- | -------- | -------- | | TiDB | [`tls-version`](/tidb-configuration-file.md#tls-version) | 修改 | 默认值为空，TiDB 默认支持的 TLS 版本从 `TLS1.1` 及更高提升为 `TLS1.2` 及更高。 | -| TiKV | [`blob-file-compression`](/tikv-configuration-file.md#blob-file-compression) | 修改 | Titan 中 value 所使用的压缩算法。从 v7.6.0 开始，默认采用 `zstd` 压缩算法。 | +| TiKV | [`blob-file-compression`](/tikv-configuration-file.md#blob-file-compression) | 修改 | 设置 Titan 中 value 所使用的压缩算法。从 v7.6.0 开始，默认采用 `zstd` 压缩算法。 | | TiKV | [`rocksdb.defaultcf.titan.min-blob-size`](/tikv-configuration-file.md#min-blob-size) | 修改 | 从 TiDB v7.6.0 开始，新建集群默认值为 `32KB`。对于已有集群升级到 v7.6.0 版本的情况，默认值为 `1KB` 保持不变。 | | TiKV | [`rocksdb.titan.enabled`](/tikv-configuration-file.md#enabled) | 修改 | 开启 Titan 开关。v7.5.0 及更早的版本默认值为 `false`。从 v7.6.0 开始，新建集群默认值是 `true`，已有集群升级到 v7.6.0 或更高版本则会维持原有的配置。 | | TiDB Lightning | [`tidb.pd-addr`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-任务配置) | 修改 | 配置 PD Server 的地址，从 v7.6.0 开始支持设置多个地址。 | -| TiDB Lightning | [`block-size`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-任务配置) | 新增 | 控制物理导入模式 (`backend='local'`) 中本地文件排序的 I/O 块大小。默认值为 `16KiB`。当 IOPS 成为瓶颈时，可以调大该参数的值以缓解 Disk IOPS，从而提升性能。 | +| TiDB Lightning | [`block-size`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-任务配置) | 新增 | 控制物理导入模式 (`backend='local'`) 中本地文件排序的 I/O 区块大小。默认值为 `16KiB`。当 IOPS 成为瓶颈时，可以调大该参数的值以缓解磁盘 IOPS，从而提升数据导入性能。 | +| TiKV | [`gc.num-threads`](/tikv-configuration-file.md#num-threads-从-v760-版本开始引入) | 新增 | 设置当 `enable-compaction-filter` 为 `false` 时 GC 的线程个数。默认值为 `1`。 | | TiKV | [`raftstore.periodic-full-compact-start-times`](/tikv-configuration-file.md#periodic-full-compact-start-times-从-v760-版本开始引入) | 新增 | 设置 TiKV 启动周期性全量数据整理 (Compaction) 的时间。默认值 `[]` 表示默认情况下禁用周期性全量数据整理。 | | TiKV | [`raftstore.periodic-full-compact-start-max-cpu`](/tikv-configuration-file.md#periodic-full-compact-start-max-cpu-从-v760-版本开始引入) | 新增 | 设置 TiKV 执行周期性全量数据整理时的 CPU 使用率阈值，默认值为 `0.1`。 | | TiKV | [`zstd-dict-size`](/tikv-configuration-file.md#zstd-dict-size) | 新增 | 指定 `zstd` 字典大小，默认值为 `0KB`，表示关闭 `zstd` 字典压缩。 | | BR | `--granularity` | 新增 | 通过设置 `--granularity="coarse-grained"` 启用粗粒度的 Region 打散算法（实验特性）进行恢复，加快大规模 Region 场景下的 Region 恢复速度。 | | BR | `--tikv-max-restore-concurrency` | 新增 | 设置启用粗粒度的 Region 打散算法时，单 TiKV 节点的下载任务并发度。 | -| TiCDC | [`encoding-worker-num`](/ticdc/ticdc-changefeed-config.md) | 新增 | 控制 redo 模块中编解码 worker 的数量，默认值为 16。 | -| TiCDC | [`flush-worker-num`](/ticdc/ticdc-changefeed-config.md) | 新增 | 控制 redo 模块中上传文件 worker 的数量，默认值为 8。 | | TiCDC | [`compression`](/ticdc/ticdc-changefeed-config.md) | 新增 | 设置 redo log 文件的压缩行为。 | +| TiCDC | [`encoding-worker-num`](/ticdc/ticdc-changefeed-config.md) | 新增 | 控制 redo 模块中编解码 worker 的数量，默认值为 `16`。 | +| TiCDC | [`flush-worker-num`](/ticdc/ticdc-changefeed-config.md) | 新增 | 控制 redo 模块中上传文件 worker 的数量，默认值为 `8`。 | | TiCDC | [`sink.cloud-storage-config`](/ticdc/ticdc-changefeed-config.md) | 新增 | 设置同步数据到对象存储时自动清理历史数据的功能。 | ### 系统表 @@ -321,8 +313,6 @@ TiDB 版本：7.6.0 - `Request_unit_write`：执行语句消耗的总写 RU。 - `Time_queued_by_rc`：执行语句过程中等待可用资源的总耗时。 -### 其他 - ## 离线包变更 从 v7.6.0 开始，`TiDB-community-server` [二进制软件包](/binary-package.md)中新增代理组件 [TiProxy](/tiproxy/tiproxy-overview.md) 的安装包 `tiproxy-{version}-linux-{arch}.tar.gz`。 @@ -387,7 +377,7 @@ TiDB 版本：7.6.0 + TiDB Lightning - 支持配置多个 PD 地址以增强稳定性 [#49515](https://github.com/pingcap/tidb/issues/49515) @[mittalrishabh](https://github.com/mittalrishabh) - - 支持通过配置参数 `block-size` 来控制 TiDB Lightning 本地文件排序的 I/O 块大小，提升性能 [#45037](https://github.com/pingcap/tidb/issues/45037) @[mittalrishabh](https://github.com/mittalrishabh) + - 支持通过配置参数 `block-size` 来控制 TiDB Lightning 本地文件排序的 I/O 区块大小，提升数据导入性能 [#45037](https://github.com/pingcap/tidb/issues/45037) @[mittalrishabh](https://github.com/mittalrishabh) ## 错误修复 @@ -506,7 +496,7 @@ TiDB 版本：7.6.0 - 修复 TiFlash 错误处理 enum 偏移量为 0 的问题 [#8311](https://github.com/pingcap/tiflash/issues/8311) @[solotzg](https://github.com/solotzg) - 修复表达式 `INET_NTOA()` 中的兼容性问题 [#8211](https://github.com/pingcap/tiflash/issues/8211) @[solotzg](https://github.com/solotzg) - 修复在 stream 读时扫描多个分区表可能导致潜在的 OOM 问题 [#8505](https://github.com/pingcap/tiflash/issues/8505) @[gengliqi](https://github.com/gengliqi) - - 修复成功执行的短查询打印过多的信息日志的问题 [#8592](https://github.com/pingcap/tiflash/issues/8592) @[windtalker](https://github.com/windtalker) + - 修复成功执行的短查询打印过多信息日志的问题 [#8592](https://github.com/pingcap/tiflash/issues/8592) @[windtalker](https://github.com/windtalker) - 修复 TiFlash 在停止时可能崩溃的问题 [#8550](https://github.com/pingcap/tiflash/issues/8550) @[guo-shaoge](https://github.com/guo-shaoge) - 修复 `GREATEST` 或 `LEAST` 函数在包含常量字符串参数时，可能发生的随机无效内存访问的问题 [#8604](https://github.com/pingcap/tiflash/issues/8604) @[windtalker](https://github.com/windtalker)