Mon, Mar 1, 2021

TiDB Monthly Update for February 2021

Releases

We have two releases this month:

New features
- Support the utf8_unicode_ci and utf8mb4_unicode_ci collations
- Support the cast_year_as_time collation
- Add a Coprocessor thread pool to queue Coprocessor requests for execution, which avoids out of memory (OOM) in some cases, and add the cop_pool_size and batch_cop_pool_size configuration items with the default values of NumOfPhysicalCores * 2
Improvements
- Reorder inner joins that are simplified from outer joins
- Add metrics of server information for DBaaS
- Report RocksDB metrics to TiDB
Bug fixes

New features
- Support configuring durations for leader election
- Add the tidb_cluster label for the scrape jobs in TidbMonitor to support monitoring multiple clusters
- Support setting customized store labels according to the node labels
Improvements
- Add TiFlash rolling upgrade logic to avoid all TiFlash stores being unavailable at the same time during the upgrade
- Retrieve the Region leader count from TiKV Pod directly instead of from PD to get the accurate count

Blog posts

Wenbo Zhang's article Linux Kernel vs. Memory Fragmentation (Part I) introduced some common extensions to the buddy allocator that helped prevent memory fragmentation in the Linux 3.10 kernel, the principle of memory compaction, how to view the fragmentation index, and how to quantify the latency overheads caused by memory compaction.

In TiGraph: 8,700x Computing Performance Achieved by Combining Graphs + the RDBMS Syntax, Heng Long, Shuang Chen, and Wenjun Huang, the second prize winners of TiDB Hackathon 2020, shared TiGraph's architecture, its benchmarks, their project innovations, potential uses for TiGraph, and their future plans.

JD Cloud database team wrote an article TiDB on JD Cloud: A Cloud-native Distributed Database Service to introduce Cloud-TiDB, a distributed database service on the cloud in cooperation with PingCAP.

Leitao Guo, the database and middleware manager at iQIYI in his article How to Efficiently Choose the Right Database for Your Applications shared with you what criteria to use for selecting a database, what databases they used at iQIYI, some decision models to help you efficiently pick a database, and tips for choosing your database.

In Celebrating One Year of Chaos Mesh: Looking Back and Ahead, Cwen Yin and Calvin Weng shared with you how Chaos Mesh had grown and changed in the past year and also discussed its future goals and plans.