Benchmarks

Looking deeper into InnoDB’s problem with many row versions

A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single row. Today I wanted to look a bit deeper into the problem, which I also filed as a bug. First […]

Hyper-threading – how does it double CPU throughput?

The other day a customer asked me to do capacity planning for their web server farm. I was looking at the CPU graph for one of the web servers that had Hyper-threading switched ON and thought to myself: “This must be quite a misleading graph – it shows 30% CPU usage. It can’t really be […]

MySQL performance implications of InnoDB isolation modes

Over the past few months I’ve written a couple of posts about dangerous debt of InnoDB Transactional History and about the fact MVCC can be the cause of severe MySQL performance issues. In this post I will cover a related topic – InnoDB Transaction Isolation Modes, their relationship with MVCC (multi-version concurrency control) and how […]

How small changes impact complex systems – MySQL example

If you’ve been studying complex systems you know what minor changes might cause consequences of much greater proportions, sometimes causing some effects that are not easily explained at first. I recently ran across a great illustration of such behavior while doing MySQL benchmarks which I thought would be interesting to share. I’m using a very […]

Streamlined Percona XtraDB Cluster (or anything) testing with Consul and Vagrant

Introducing Consul I’m always interested in what Mitchell Hashimoto and Hashicorp are up to, I typically find their projects valuable.  If you’ve heard of Vagrant, you know their work. I recently became interested in a newer project they have called ‘Consul‘.  Consul is a bit hard to describe.  It is (in part): Highly consistent metadata […]

MySQL benchmarking: Know your baseline variance!

Often enough I find MySQL benchmark results where the difference between results is 1% or even less and some conclusions are drawn. Now it is not that 1% is not important – especially when you’re developing the product you should care about those 1% improvements or regressions because they tend to add up. However with […]

MySQL’s INNODB_METRICS table: How much is the overhead?

Starting with MySQL 5.6 there is an INNODB_METRICS table available in INFORMATION_SCHEMA which contains some additional information than provided in the SHOW GLOBAL STATUS output – yet might be more lightweight than PERFORMANCE_SCHEMA. Too bad INNODB_METRICS was designed during the Oracle-Sun split under MySQL leadership and so it covers only InnoDB counters. I think this […]

RDS for Aurora unveiled at AWS re:Invent

One of the big announcements at the Amazon Web Services re:Invent 2014 conference this week was the unveiling of Aurora. The result of years of internal work, Aurora, currently in preview, is a MySQL 5.6-compatible option that “combines the speed and availability of high-end commercial databases with the simplicity and cost-effectiveness of open source databases” on […]

MySQL and Openstack deep dive talk at OpenStack Paris Summit (and more!)

I will present a benchmarking talk next week (Nov. 4) at the OpenStack Paris Summit with Jay Pipes from Mirantis. In order to be able to talk about benchmarking, we had to be able to set up and tear down OpenStack environments really quickly. For the benchmarks, we are using a deployment on AWS (ironically) […]

Generating test data from the mysql> prompt

There are a lot of tools that generate test data.  Many of them have complex XML scripts or GUI interfaces that let you identify characteristics about the data. For testing query performance and many other applications, however, a simple quick and dirty data generator which can be constructed at the MySQL command line is useful. […]