Percona is glad to announce the release of Percona Monitoring Plugins 1.0.3 for MySQL — high-quality components to add enterprise-grade MySQL monitoring and graphing capabilities to your existing in-house, on-premises monitoring solutions. The components are designed to integrate seamlessly with widely deployed solutions such as Nagios and Cacti, and are delivered in the form of [...]
Understanding the maximum number of columns in a MySQL table
This post was initially going to be two sets of polls: “What is the maximum number of columns in MySQL?” and “What is the minimum maximum number of columns in MySQL?”. Before you read on, ponder those questions and come up with your own answers… and see if you’re right or can prove me wrong! [...]
MySQL 5.6 Compatible Percona Toolkit 2.2 Released
A new Percona Toolkit series has been released: Percona Toolkit 2.2 for MySQL 5.6. Several months in the making and many new features, changes, and improvements make this a great new series. It replaces the 2.1 series for which we plan to do only one more bug fix release (as 2.1.10) then retire. 2.2 is [...]
Why do we care about MySQL Performance at High Concurrency?
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 [...]
Percona Server on the Raspberry Pi: Your own MySQL Database Server for Under $80
There are many reasons for wanting a small MySQL database server: You’re a uni student who wants to learn the SQL language better and needs a mini-testbox You’re a Windows user who wants to play around with Percona Server on Linux You’re a corporate application developer who wants a small SQL development & test box [...]
Analyzing Slow Query Table in MySQL 5.6
Next week I’m teaching an online Percona Training class, called Analyzing SQL Queries with Percona Toolkit. This is a guided tour of best practices for pt-query-digest, the best tool for evaluating where your database response time is being spent. This month we saw the GA release of MySQL 5.6, and I wanted to check if any [...]
Is MySQL 5.6 slower than MySQL 5.5?
There have been a number reports/benchmarks showing MySQL 5.6 to be slower than MySQL 5.5 on variety of workloads. There are many possible reasons and I believe we will learn about many of them in the next few weeks and months as MySQL 5.6 is starting to get production battle-tested and there is inflow of [...]
Can’t Create Thread: Errno 11 (A Tale of Two Ulimits)
Recently some of my fellow Perconians and I have noticed a bit of an uptick in customer cases featuring the following error message:
1 2 | SQLSTATE[HY000] [1135] 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 [...]

