The latest from the MySQL community

Ask anyone who runs a multi-node MySQL Galera Cluster in production about their worst night. Almost nobody says write-set replication was wrong. They say something closer to this:

“All queries piling up… no error messages in logs.”

Twenty minutes of downtime, ended only when a human picked a node to kill. (codership-team)

Or the flow-control stall where writes time out and wsrep_flow_control_sent still reads 0, so there’s nothing to alert on and nothing to write in the post-mortem. (codership-team)

You have your own version of these. You didn’t need mine.

And here’s the thing about all of them: the root cause is usually not Galera. It’s flashcache, or a shadowed wsrep_provider_options line, or DNS resolving to …

As you are probably aware, Red Hat Enterprise Linux 6 (RHEL 6 or EL 6 in short) officially reached “End of Life” (EOL) on 2020-11-30 and is now in the so-called Extended Life Phase, which basically means that Red Hat will no longer provide bug fixes or security fixes.

Even though EL 6 and its compatible derivatives like CentOS 6 had reached EOL some time ago already, we continued providing binary builds for selected MySQL-related products for this platform.

However, this became increasingly difficult, as the MySQL code base continued to evolve and now depends on tools and functionality that are no longer provided by the operating system out of the box. This meant we already had to perform several modifications in order to prepare binary builds for this platform, e.g. installing custom compiler versions or newer versions of various system …

In Percona Support we spend a few hours per week doing Labs: short collective projects, not directly related to the tickets. One of our last labs was about to get ready for the winter holiday season which means preparing the tree and decorating it. To do it we used our favorite tools: MySQL, and ASCII art (https://en.wikipedia.org/wiki/ASCII_art). As a result, we created a function that prints into the terminal a New Year Tree (https://en.wikipedia.org/wiki/New_Year_tree) and decorates it with symbols we want. For example, to create a three-level tree, decorated with starts, call the function as follow:

$ mysql ny_tree -e "select ny_tree(3, '*')" --vertical --skip-column-names -s
*************************** 1. row ***************************

   /\
  /__\
  /* \
 /____\
 /  * \
/______\
   ||

Since MySQL supports Unicode you can use any symbol, having it has …

As we’ve communicated in our blog post in May, the TokuDB Storage Engine has been marked as “deprecated” in Percona Server for MySQL 8.0. It will be removed in a future version (Percona Server for MySQL 8.0.28, expected to ship in Q1 2022).

With the release of Percona Server for MySQL 8.0.26, the storage engine will still be included in the binary builds and packages but will be disabled by default. If you are upgrading from a previous version, the TokuDB Storage Engine plugin will fail with an error message at server startup if it is installed.

You will still be able to re-enable it manually so that you can perform the necessary migration steps.

Re-enabling the TokuDB …

We’re excited to share that Marcelo Altmann from the Percona Server Engineering Team has just been promoted from Oracle ACE Associate to Oracle ACE.

Congratulations!

The Oracle ACE Program recognizes and rewards community members for their technical contributions to the Oracle community.

Marcelo initially joined Percona as a senior support engineer in our global services organization, where he helped customers with running their MySQL-based environments. In early 2020, he joined our Server Engineering team and has been actively involved in the development of Percona Server for MySQL and Percona …

Due to CVE-2020-29488, Percona XtraBackup is modifying how xbstream handles absolute paths to prevent malicious file injections. Like the tar archiving utility, the new behavior removes the leading ‘/’ character and references to the parent directory.

Fixes are available in Percona XtraBackup versions:

>= 2.4.22

>= 8.0.23-16.0

For example, ../../../d1/../d2/h.txt will be saved in the stream with the relative path ./d2/h.txt.

The updated function provides a warning when creating a stream with a file with an absolute path:

$ xbstream -c /tmp/data

xbstream: Removing leading '/' from member names

The function also will not extract …

April 29, 2020 – Percona is pleased to announce the release of Percona XtraDB Cluster 8.0. This release, based on Percona Server for MySQL 8.0 and Galera 4, brings together the best features of these and other products to deliver an open-source high availability MySQL solution that helps enterprises minimize unexpected downtime and data loss, improve data security, and ensure data integrity of your database environments supporting your critical business applications in the most demanding public, private, and hybrid cloud environments.

Percona XtraDB Cluster 8.0 enables enterprises to improve data security and ensure data integrity with new encryption and streaming replication features. …