MySQL Performance Blog

During the last couple of months I have been involved in an unusually high amount of performance audits for e-commerce applications running with Magento. And although the systems were quite different, they also had one ...

The post The MySQL query cache: Worst enemy or best friend? appeared first on MySQL Performance Blog.

Today’s episode is all about Valgrind – from the pro’s to the con’s, from the why to the how! This episode will be of interest to anyone who is or wants to work with Valgrind on ...

The post MySQL QA Episode 11: Valgrind Testing: Pro’s, Con’s, Why and How appeared first on MySQL Performance Blog.

In my recent benchmarks for MongoDB, we can see that the two engines WiredTiger and TokuMX struggle from periodical drops in throughput, which is clearly related to a checkpoint interval – and therefore I correspond ...

The post InnoDB checkpoint strikes back appeared first on MySQL Performance Blog.

Lately I saw many cases when users specified option [crayon-55b9f5d1a40f1439677978-i/]  to print out a statement representation of row events in MySQL binary logs just to get nothing. Reason for this is obvious: option [crayon-55b9f5d1a4108596981142-i/]  does not convert row events into its string representation, this is job of option [crayon-55b9f5d1a4110690456505-i/] . But why users mix these […]

Welcome to MySQL QA Episode 9. This episode will go more in-depth into reducer.sh: Reducing Testcases for Experts: multi-threaded reducer.sh We will explore how to use reducer.sh to do true multi-threaded testcase reduction – a world’s first. Topics: Expert configurable variables & their default reducer.sh settings PQUERY_MULTI PQUERY_MULTI_THREADS PQUERY_MULTI_CLIENT_THREADS PQUERY_MULTI_QUERIES PQUERY_REVERSE_NOSHUFFLE_OPT Full-screen viewing @ 720p resolution […]

Thank you for attending my July 15 webinar, “Creating Best in Class Backup solutions for your MySQL environment.” Due to the amount of content we discussed and some minor technical difficulties faced near the end of webinar we have decided to cover the final two slides of the presentation along with the questions asked by […]

I recently worked with a customer who had a weird issue: when their MySQL server was started (Percona Server 5.5), if they try to run service mysql start a second time, the init script was not able to detect that an instance was already running. As a result, it tried to start a second instance […]

The post SELinux and the MySQL init script appeared first on MySQL Performance Blog.

Welcome to MySQL QA Episode #7 – Reducing Testcases for Beginners: single-threaded reducer.sh! In this episode we’ll learn how to use reducer.sh. Topics discussed; reducer.sh introduction/concepts Basic configurable variables & their default reducer.sh settings INPUTFILE options MODE=x TEXT=”text” WORKDIR_LOCATION & WORKDIR_M3_DIRECTORY MYEXTRA MYBASE PQUERY_MOD & PQUERY_LOC MODE5_COUNTTEXT, MODE5_ADDITIONAL_TEXT & MODE5_ADDITIONAL_COUNTTEXT How to learn more about each […]

As you may know, Tokutek is now part of Percona and I would like to explain some internals of TokuDB and TokuMX – what performance benefits they bring, along with further optimizations we are working on. However, before going into deep details, I feel it is needed to explain the fundamentals of Key-Value store, and […]

Beware the SST In Percona XtraDB Cluster (PXC) I often run across users who are fearful of SSTs on their clusters. I’ve always maintained that if you can’t cope with a SST, PXC may not be right for you, but that doesn’t change the fact that SSTs with multiple Terabytes of data can be quite […]

In this post I’ll share the results of a sysbench-mongodb benchmark I performed on my server. I compared MMAP, WiredTiger, RocksDB and TokuMXse (based on MongoDB 3.0) and TokuMX (based on MongoDB 2.4) in an IO-intensive workload. The full results are available here, and below I’ll just share the summary chart: I would like to […]

Have you ever wondered what could happen if your MySQL database goes down? Although it’s evident such a crash will cause downtime – and surely some business impact in terms of revenue – can you do something to reduce this impact? The simple answer is “yes” by doing regular backups (of course) but are you […]