Monthly Archives - June 2015

Playing with Percona XtraDB Cluster in Docker

Like any good, thus lazy, engineer I don’t like to start things manually. Creating directories, configuration files, specify paths, ports via command line is too boring. I wrote already how I survive in case when I need to start MySQL server (here). There is also the MySQL Sandbox which can be used for the […]

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Practical MySQL Performance Optimization (July 2 webinar)

Applications often become impacted by MySQL performance. Optimization is the obvious solution but where to start? Join me on July 2 at 11 a.m. Pacific and I’ll show you how to optimize MySQL in a practical way – spending time on what gives you the best return. Many of you have heard me talk […]

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Tips for avoiding malware from a lesson learned

In a recent article on the Percona blog, I recommended readers to a tool called CamStudio for making technical screen recordings. The blog post was very popular and got 300+ Facebook likes in a short time. Providentially though, a reader commented that the installer (as downloaded from the project website) installed “pretty annoying adware […]

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Oracle license revenue and the MySQL ecosystem

Oracle was in the news recently with the story of its license revenue declining as much as 17% in the recent quarter. This is blamed on transitioning to the cloud in some publications, but others, such as Bloomberg and TechRepublic, look deeper, seeing open source software responsible for the bulk of it.
Things are especially […]

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Percona XtraDB Cluster (PXC): How many nodes do you need?

A question I often hear when customers want to set up a production PXC cluster is: “How many nodes should we use?”
Three nodes is the most common deployment, but when are more nodes needed? They also ask: “Do we always need to use an even number of nodes?”
This is what we’ll clarify in this […]

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Percona Monitoring Plugins 1.1.5 release

Percona is glad to announce the release of Percona Monitoring Plugins 1.1.5.
Changelog:

Added more DB instance classes to pmp-check-aws-rds.py (issue 1398911)
Added configurable query period and average time to pmp-check-aws-rds.py (issue 1436943)
Added region support to pmp-check-aws-rds.py (issue 1442980)
Added an option to alert when server is not configured as replica to pmp-check-mysql-replication-delay (issue 1357017)
Added an option to […]

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Q&A: High availability when using MySQL in the cloud

Last week I hosted a webinar on using MySQL in the cloud for High Availability (HA) alongside 451 Research analyst Jason Stamper. You can watch the recording and also download the slides (free) here. Just click the “Register” button at the end of that page.
We had several excellent questions and we didn’t have time […]

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Getting EXPLAIN information from already running queries in MySQL 5.7

When a new version of MySQL is about to be released we read a lot of blog posts about the performance and scalability improvements. That’s good but sometimes we miss some small features that can help us a lot in our day-to-day tasks. One good example is the blog post that Aurimas wrote about […]

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Update on the InnoDB double-write buffer and EXT4 transactions

IMPORTANT: DON’T TRY THIS IN PRODUCTION. As demonstrated by Marko (see comments), it may corrupt your data.
In a post, written a few months ago, I found that using EXT4 transactions with the “data=journal” mount option, improves the write performance significantly, by 55%, without putting data at risk. Many people commented on the post mentioning […]

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Speed up GROUP BY queries with subselects in MySQL

We usually try to avoid subselects because sometimes they force the use of a temporary table and limits the use of indexes. But, when is good to use a subselect?
This example was tested over table a (1310723 rows), b, c and d ( 5 rows each) and with MySQL version 5.5 and 5.6.
Let’s suppose […]

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