For this post I’m going to shamelessly exploit the litany of technical problems SimCity players encountered earlier this month and a few examples of how Thread Pool for MySQL and Percona Server for MySQL can help to prevent such incidents. Users of SimCity, a city-building and urban planning simulation video game, encountered network outages, issues with […]
Last time I wrote about memory allocators and how they can affect MySQL performance in general. This time I would like to explore this topic from a bit different angle: What impact does the number of processor cores have on different memory allocators and what difference we will see in MySQL performance in this scenario? […]
In many MySQL Benchmarks we can see performance compared with rather high level of concurrency. In some cases reaching 4,000 or more concurrent threads which hammer databases as quickly as possible resulting in hundreds or even thousands concurrently active queries. The question is how common is it in production ? The typical metrics to use […]
Based on a lot of surprising comments about my MySQL 5.5 vs 5.6 performance post I decided to perform deeper investigation to see where my results could go possibly wrong. I had set up everything to be as simple as possible to get maximally repeatable results. I did Read Only ran which is typically a […]
About a month ago, we held a bug raffle for Percona Toolkit 2.1.9. The turnout was good and the resulting release is worth upgrading to, especially if you were affected by the backwards-incompatible changes to pt-heartbeat in 2.1.8. Here are the release notes for Percona Toolkit 2.1.9 which highlight the bugs fixed: Percona Toolkit 2.1.9 has been released. […]
Recently some of my fellow Perconians and I have noticed a bit of an uptick in customer cases featuring the following error message:
SQLSTATE[HY000]  Can't create a new thread (errno 11); if you are not
out of available memory, you can consult the manual for a possible OS-dependent bug.
The canonical solution to this issue, if you do a bit of Googling, is to increase the number of processes / threads available to the MySQL user, typically by adding a […]
Today I gave a presentation on “Read/Write Splitting with PHP” for Percona Webinars. If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially to folks who asked the great questions. I answered as many as I could during the session, but here are […]
Earlier this week, Cédric blogged about how easy we can get confused between a covering index and a full index scan in the EXPLAIN output. While a covering index (seen with EXPLAIN as Extra: Using index) is a very interesting performance optimization, a full index scan (type: index) is according to the documentation the 2nd […]
Quality Assurance: Percona Server Development Now Monitored by Automated Sysbench Performance Regression Checks!
Continuous integration of new features and bug fixes is great – but what if a small change in seemingly insignificant code causes a major performance regression in overall server performance? We need to ensure this does not happen. That said, performance regressions can be hard to detect. They may hide for some time (or be […]
MySQL server intensively uses dynamic memory allocation so a good choice of memory allocator is quite important for the proper utilization of CPU/RAM resources. Efficient memory allocator should help to improve scalability, increase throughput and keep memory footprint under the control. In this post I’m going to check impact of several memory allocators on the […]