Percona announces the release of Percona Monitoring Plugins 1.1.8.

Changelog

• Add MySQL 5.7 support
• Changed a canary check to use timestamp.now() and return a timedelta.seconds
• Remove an additional condition for the Dictionary memory allocated
• Fixed a false-positive problem when the calculated delay was less than 0 and the -m was not set.
• Fixed the problem where slaves would alert due to deadlocks on the master.
• If using pt-heartbeat, get_slave_status was only called when the -s option is set to …

In this blog post, I’ll look into four ways MySQL executes GROUP BY. 

In my previous blog post, we learned that indexes or other means of finding data might not be the most expensive part of query execution. For example, MySQL GROUP BY could potentially be responsible for 90% or more of the query execution time. 

The main complexity when MySQL executes GROUP BY is computing aggregate functions in a GROUP BY statement. How this works is shown in the documentation for UDF Aggregate Functions. As we see, the requirement is that UDF functions get all values that constitute the single group one …

After dealing with Windows performance, I switched to MySQL Cluster Configurator (MCC for short) project. This was quite a change for me having to deal with Python back-end and JavaScript front-end, languages I was not so familiar with.

For the history of the project, please refer to Andrew's blog post for I will concentrate on changes made in new version.

There are many exciting new features in MySQL Cluster 7.6.4DMR including new MCC. To download MySQL Cluster 7.6.4DMR, please go to Development Releases tab. To see what's new in 7.6.4DMR, please follow this link.

MySQL Cluster Configurator in short With a single …

Things I look for when optimising or debugging a Linux OS:

• IOschedular (noop or deadline)
• Linux Kernel > 3.18 (multi queuing)
• IRQbalance > 1.0.8
• File System: noatime, nobarrier
  • ext4: data=ordered
  • xfs: 64k
  • logfiles in different partition (if possible)
• Swapiness (0 or 1, depending)
• Jemalloc (if needed)
• Transparent hugepages - disabled
• Ulimit (open files) >1000
• Security
  • IPtables
  • PAM security
• Raid Controller/Smart HBA
  • write-cache enabled
  • battery backed
  • For HP servers: hpssacli controller all show (detail|status)
  • Tweak cache-ratio to 50/50 or 75/25 (and test)
  …

Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

Percona Live Santa Clara 2018 update: tutorials have been picked, and the schedule/press release should be announced by next week. We’ve (the committee) rated over 300+ talks, and easily 70% of the schedule should go live next week as well.

There’s a lot happening for FOSDEM this week — so expect a longer report of some sort next week.

A friend, Yanwei Zhou, DBA at Qunar in China, gave an excellent presentation in Chinese on how they use Percona Toolkit. …

Dear MySQL users,

MySQL Connector/Python 8.0.6-rc is the first release candidate version
of the MySQL Connector Python 8.0 series. This series adds support for
the new X DevAPI. The X DevAPI enables application developers to write
code that combines the strengths of the relational and document models
using a modern, NoSQL-like syntax that does not assume previous
experience writing traditional SQL.

To learn more about how to write applications using the X DevAPI, see
http://dev.mysql.com/doc/x-devapi-userguide/en/. For more information
about how the X DevAPI is implemented in MySQL Connector/Python, and its
usage, see http://dev.mysql.com/doc/dev/connector-python.

Please note that the X DevAPI requires MySQL Server version 5.7.12 or
higher with the X Plugin enabled. For general documentation about how to
get started using MySQL as a document store, …

Percona recently released Percona Server with MyRocks as GA. You can see how Facebook explains wins they see in production with MyRocks. Now if you use Percona repositories, you can simply install MyRocks plugin and enable it with ps-admin --enable-rocksdb.

There are some major and minor differences when comparing it to typical InnoDB deployments, and I want to highlight them here. The first important difference is that MyRocks (based on RocksDB) uses  …

Percona announces the release of Percona Monitoring and Management 1.7.0. (PMM ) is a free and open-source platform for managing and monitoring MySQL and MongoDB performance. You can run PMM in your own environment for maximum security and reliability. It provides thorough time-based analysis for MySQL and MongoDB servers to ensure that your data works as efficiently as possible.

This release features improved support for external services, which enables a PMM Server to store and display metrics for any available Prometheus exporter. For example, you could deploy the postgres_exporter and use PMM’s external services feature to store PostgreSQL metrics in PMM. Immediately, you’ll see these new metrics in …

The Aurora hash join feature for relational databases has been around for a while now. But unlike MySQL Block Nested Loop algorithm, an Aurora hash join only caters to a specific number of use cases. When implemented with the optimizer properly, they can provide great benefits with certain workloads. Below we’ll see a brief example of a quick win.

This new feature is available in Aurora lab mode version 1.16. Because this is a lab feature, it’s important to make sure to test your queries before upgrading, especially if you are looking to scale up to the new R4 instances before the Superbowl to avoid hitting the same problem I discuss below.

When lab mode is enabled and

hash_join

  is ON, you can verify the optimizer feature from the

optimizer_switch

 variable:

Dear MySQL users,

MySQL Connector/Java 8.0.9-rc is the first Release Candidate
of the 8.0 branch of MySQL Connector/J, providing an insight into
upcoming features. It is suitable for use with MySQL Server versions
5.5, 5.6, 5.7, and 8.0. It supports the Java Database Connectivity
(JDBC) 4.2 API.

This release includes the following new features and changes, also
described in more detail on

https://dev.mysql.com/doc/relnotes/connector-j/8.0/en/news-8-0-9.html

MySQL Connectors and other MySQL client tools and applications now
synchronize the first digit of their version number with the (highest)
MySQL server version they support.
This change makes it easy and intuitive to decide which client version
to use for which server version.

As always, we recommend that you check the “CHANGES” file in the download
archive to be aware of …