From ef2eeaf2fe06a0252590540deea3f0975ca732fa Mon Sep 17 00:00:00 2001 From: TomShawn <41534398+TomShawn@users.noreply.github.com> Date: Fri, 25 Jun 2021 14:39:38 +0800 Subject: [PATCH 1/4] Add a missing sentence in 5.1.0 release notes --- releases/release-5.1.0.md | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/releases/release-5.1.0.md b/releases/release-5.1.0.md index 07eccea9a1447..dec9d39088fcd 100644 --- a/releases/release-5.1.0.md +++ b/releases/release-5.1.0.md @@ -22,7 +22,7 @@ In v5.1, the key new features or improvements are as follows: > **Note:** > -> When upgrading from an earlier TiDB version to v5.1, if you want to know the compatibility change notes of all intermediate versions, you can check the [Release Notes](/releases/release-notes.md) for the corresponding version. +> When upgrading from an earlier TiDB version to v5.1, if you want to know the compatibility change notes of all intermediate versions, you can check the [Release Notes](/releases/release-notes.md) for the corresponding version. ### System variables @@ -68,11 +68,13 @@ In v5.1, the key new features or improvements are as follows: ### SQL -- Support the Common Table Expression (CTE) feature of MySQL 8.0, which empowers TiDB with the capability of querying hierarchical data recursively or non-recursively. +- Support the Common Table Expression (CTE) feature of MySQL 8.0, which empowers TiDB with the capability of querying hierarchical data recursively or non-recursively. - This feature meets the needs of using tree queries to implement application logics in multiple sectors such as human resources, manufacturing, financial markets, and education. [User document](/sql-statements/sql-statement-with.md), [#17472](https://github.com/pingcap/tidb/issues/17472) + This feature meets the needs of using tree queries to implement application logics in multiple sectors such as human resources, manufacturing, financial markets, and education. -- Support the dynamic privilege feature of MySQL 8.0. + In TiDB, you can apply the `WITH` statement to use Common Table Expressions. [User document](/sql-statements/sql-statement-with.md), [#17472](https://github.com/pingcap/tidb/issues/17472) + +- Support the dynamic privilege feature of MySQL 8.0. Dynamic privileges are used to limit the `SUPER` privilege and provide TiDB with more flexible privilege configuration for more fine-grained access control. For example, you can use dynamic privileges to create a user account that can only perform `BACKUP` and `RESTORE` operations. From 12c718b75fcb8feb55b6e0645fdb4cdc4f255cd1 Mon Sep 17 00:00:00 2001 From: TomShawn <41534398+TomShawn@users.noreply.github.com> Date: Fri, 25 Jun 2021 14:40:04 +0800 Subject: [PATCH 2/4] Update release-5.1.0.md --- releases/release-5.1.0.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/releases/release-5.1.0.md b/releases/release-5.1.0.md index dec9d39088fcd..4c50eb5a1200c 100644 --- a/releases/release-5.1.0.md +++ b/releases/release-5.1.0.md @@ -151,7 +151,7 @@ In v5.1, the key new features or improvements are as follows: - Large amounts of data writes cause OOM problems in TiCDC. - Reduce the possibility of TiCDC replication interruption in the following scenarios: [project#11](https://github.com/pingcap/ticdc/projects/11) - + - Replication interruption when the network is unstable - Replication interruption when some TiKV/PD/TiCDC nodes are down @@ -203,7 +203,7 @@ To learn more about the information and how to disable this behavior, refer to [ - Support `Union All`, `TopN`, and `Limit` functions - Support the Cartesian product including left outer join and semi anti join in MPP mode - Optimize lock operations to avoid that running DDL statements and read operations are blocked by each other - - Optimize cleanup of expired data by TiFlash + - Optimize cleanup of expired data by TiFlash - Support further filtering of query filters on `timestamp` columns at the TiFlash storage level - Improve the startup and scalability speed of TiFlash when a large number of tables are in a cluster - Improve TiFlash compatibility when running on unknown CPUs From b7f276ae70983b3199c6360d5561e63ddf42256d Mon Sep 17 00:00:00 2001 From: TomShawn <41534398+TomShawn@users.noreply.github.com> Date: Fri, 25 Jun 2021 15:06:19 +0800 Subject: [PATCH 3/4] Update release-5.1.0.md --- releases/release-5.1.0.md | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/releases/release-5.1.0.md b/releases/release-5.1.0.md index 4c50eb5a1200c..a0b958a8d1e60 100644 --- a/releases/release-5.1.0.md +++ b/releases/release-5.1.0.md @@ -134,13 +134,11 @@ In v5.1, the key new features or improvements are as follows: + Stale read of data replicas (Experimental) - Read local replicas data directly to reduce read latency and improve the query performance - [User document](/stale-read.md), [#21094](https://github.com/pingcap/tidb/issues/21094) + Read local replicas data directly to reduce read latency and improve the query performance [User document](/stale-read.md), [#21094](https://github.com/pingcap/tidb/issues/21094) + Enable the Hibernate Region feature by default. - If a Region is in an inactive state for a long time, it is automatically set to a silent state, which reduces the system overhead of the heartbeat information between the Leader and the Follower. - [User document](/tikv-configuration-file.md#hibernate-regions)，[#10266](https://github.com/tikv/tikv/pull/10266) + If a Region is in an inactive state for a long time, it is automatically set to a silent state, which reduces the system overhead of the heartbeat information between the Leader and the Follower. [User document](/tikv-configuration-file.md#hibernate-regions)，[#10266](https://github.com/tikv/tikv/pull/10266) ### Stability @@ -150,6 +148,7 @@ In v5.1, the key new features or improvements are as follows: - If large amounts of data is accumulated during the replication interruption, exceeding 1TB, the re-replication causes OOM problems. - Large amounts of data writes cause OOM problems in TiCDC. - Reduce the possibility of TiCDC replication interruption in the following scenarios: + [project#11](https://github.com/pingcap/ticdc/projects/11) - Replication interruption when the network is unstable @@ -161,8 +160,7 @@ In v5.1, the key new features or improvements are as follows: + Add a write rate limiter for TiKV background tasks (TiKV Write Rate Limiter) - To ensure the duration stability of read and write requests, TiKV Write Rate Limiter smoothes the write traffic of TiKV background tasks such as GC and Compaction. The default value of TiKV background task write rate limiter is "0MB". It is recommended to set this value to the optimal I/O bandwidth of the disk, such as the maximum I/O bandwidth specified by the cloud disk manufacturer. - [User document](/tikv-configuration-file.md#storageio-rate-limit), [#9156](https://github.com/tikv/tikv/issues/9156) + To ensure the duration stability of read and write requests, TiKV Write Rate Limiter smoothes the write traffic of TiKV background tasks such as GC and Compaction. The default value of TiKV background task write rate limiter is "0MB". It is recommended to set this value to the optimal I/O bandwidth of the disk, such as the maximum I/O bandwidth specified by the cloud disk manufacturer. [User document](/tikv-configuration-file.md#storageio-rate-limit), [#9156](https://github.com/tikv/tikv/issues/9156) + Solve scheduling stability issues when multiple scaling tasks are performed at the same time From bf122100fc7029371e8b33b98c07f954ed3766d0 Mon Sep 17 00:00:00 2001 From: TomShawn <41534398+TomShawn@users.noreply.github.com> Date: Fri, 25 Jun 2021 15:06:51 +0800 Subject: [PATCH 4/4] Update releases/release-5.1.0.md --- releases/release-5.1.0.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/releases/release-5.1.0.md b/releases/release-5.1.0.md index a0b958a8d1e60..5cfcfa40a852d 100644 --- a/releases/release-5.1.0.md +++ b/releases/release-5.1.0.md @@ -138,7 +138,7 @@ In v5.1, the key new features or improvements are as follows: + Enable the Hibernate Region feature by default. - If a Region is in an inactive state for a long time, it is automatically set to a silent state, which reduces the system overhead of the heartbeat information between the Leader and the Follower. [User document](/tikv-configuration-file.md#hibernate-regions)，[#10266](https://github.com/tikv/tikv/pull/10266) + If a Region is in an inactive state for a long time, it is automatically set to a silent state, which reduces the system overhead of the heartbeat information between the Leader and the Follower. [User document](/tikv-configuration-file.md#hibernate-regions), [#10266](https://github.com/tikv/tikv/pull/10266) ### Stability