After we released pquery to the community, and as we started logging bug reports with pquery testcases, it quickly became clear that pquery binaries with statically compiled-in client libraries would be of great convenience, both for ourselves and for the community. (If you haven’t heard about pquery yet, read the pquery introduction blog post, come and […]
Two years ago Ovais Tariq had explained in detail what kinds of problems existed before MySQL introduced metadata locks in 5.5.3 and how these locks help to prevent them. Still, some implications of metadata locking in MySQL remain unclear for users – DBAs and even software developers that target recent MySQL versions. I’ve decided to […]
MySQL QA Episode #1: Bash/GNU Tools & Linux Upskill & Scripting Fun This episode consists of 13 parts, and an introduction. See videos below In HD quality (set your player to 720p!) Introduction Part 1: echo, ls, cp, rm, vi, cat, df, du, tee, cd, clear, uname, date, time, cat, mkdir Part 2: find, wc, sort, […]
Welcome to the MySQL QA Training Series! If you have not read our introductory blog post on pquery yet, I’d recommend reading that one first to get a bit of background. The community is enthuastic about pquery, and today I am happy to announce a full training series on pquery and more. Whether you are […]
My webinar “Multi-threaded Replication in MySQL 5.6 and 5.7″ on February 25 generated several excellent questions following the presentation (available here for playback along with the slides). I didn’t have time to answer many of the questions during the session and so in this post I answer all of them. Thanks to everyone who attended! Q: […]
From time to time people wonder how to implement roles in MySQL. This can be useful for companies having to deal with many user accounts or for companies with tight security requirements (PCI or HIPAA for instance). Roles do not exist in regular MySQL but here is an example on how to emulate them using […]
DBAs often encounter situations where they need to kill queries to ensure there are no long-running queries on a MySQL server that would impact performance. Long-running queries can be the result of many factors. Fortunately, Percona Server contains some handy tools to remove problematic MySQL processes. I will highlight all of the tools via some […]
If you use Percona Server 5.5 and you have configured it to use multiple buffer pool instances than sooner or later you’ll see the following lines on the server’s error log and chances are you’ll be worried about them:
InnoDB: detected cycle in LRU for buffer pool 5, skipping to next buffer pool.
InnoDB: detected cycle in LRU for buffer pool 3, skipping to next buffer pool.
InnoDB: detected cycle in LRU for buffer pool 7, skipping to next buffer pool.
Worry not as this is mostly harmless. It’s becoming a February tradition for me (Fernando) […]
MySQL introduced the Event Scheduler in version 5.1.6. The Event Scheduler is a MySQL-level “cron job”, which will run events inside MySQL. Up until now, this was not a very popular feature, however, it has gotten more popular since the adoption of Amazon RDS – as well as similar MySQL database as a service offerings […]
Global Transaction IDs (GTIDs) are one of my favorite features of MySQL 5.6. The main limitation is that you must stop all the servers at the same time to allow GTID-replication. Not everyone can afford to take a downtime so this requirement has been a showstopper for many people. Starting with Percona Server 5.6.22-72.0 enabling […]