Mon, Jan 4, 2021

TiDB Monthly Update for December 2020

Releases

We have five releases in this month:

TiDB 4.0.9 Release Notes
- New features
  - TiFlash supports storing the latest data of the storage engine on multiple disks (experimental)
  - TiDB Dashboard supports displaying and sorting by all fields in the SQL Statements page
  - TiDB Dashboard supports customizing the Prometheus address
- Improvements
  - Avoid the (index) merge join in a heuristic way when converting equal conditions to other conditions in TiDB
  - Differentiate the types of user variables in TiDB
  - Support setting the GOGC variable in the configuration file in TiDB
  - Add the tag to trace the source of the split command in TiKV
- Bug fixes
TiDB 3.0.20 Release Notes
- Compatibility changes
  - Deprecate the enable-streaming configuration item in TiDB
- Improvements
  - Raise an error when preparing the LOAD DATA statement
  - Add the end_point_slow_log_threshold configuration item
- Bug fixes
TiDB Data Migration 2.0.1 Release Notes
- Improvements
  - Support the relay log feature in high availability scenarios
  - Restrict the handle-error command to only handle DDL errors to avoid misuse
  - Support simultaneously connecting multiple DM-master nodes and automatically switching connected nodes in dmctl
- Bug fixes
TiDB Operator 1.1.8 Release Notes
- New features
  - Support arbitrary Volume and VolumeMount for PD, TiDB, TiKV, TiFlash, Backup and Restore, which enables using NFS or any other kubernetes-supported volume source for backup/restore workflow
- Improvements
  - Support cluster and client TLS for tidb-lightning and tikv-importer helm charts
  - Support setting additional ports for the TiDB service
- Bug fixes
TiDB Operator 1.1.9 Release Notes
- Improvement
  - Support spec.toolImage for Backup & Restore to define the image used to provide the Dumpling/TiDB Lightning binary executables
- Bug fixes

Blog posts

In PingCAP's Top 10 Posts of 2020, we took a look back at our 10 most popular posts in 2020.

We also published PingCAP 2020 Year in Review to look back at some of our important milestones and achievements that we accomplished, while we looked forward to a greater year ahead.

Will Zhang, a TiDB community member, wrote an article TiDB on KubeSphere: Release a Cloud-Native Distributed Database to the KubeSphere App Store that walked you through how to deploy TiDB on KubeSphere by app templates and release TiDB to the App Store.

In Batch Processing Massive Data Much Quicker with TiSpark, our senior solution architect Zhexuan Yang explained why TiSpark is better than the traditional batch processing solution, how you can benefit from TiSpark, and how it works.

In this monthly, our engineer Wenbo Zhang has written four articles:

Why We Switched from BCC to libbpf for Linux BPF Performance Analysis described why libbpf-tools, a collection of applications based on the libbpf + BPF CO-RE mode, is a better solution than bcc-tools and how we're using libbpf-tools at PingCAP.
Why We Disable Linux's THP Feature for Databases described how THP causes performance to fluctuate, the typical symptoms, and our recommended solutions.
In Tips and Tricks for Writing Linux BPF Applications with libbpf, Zhang shared his experience about writing Berkeley Packet Filter (BPF) applications with libbpf. He hopes that this article is helpful to people who are interested in libbpf and inspires them to further develop and improve BPF applications with libbpf.
How to Trace Linux System Calls in Production with Minimal Impact on Performance introduced perf and traceloop, two commonly used command-line tools, to help you trace system calls in a production environment.