Author - Juan Arruti

A Simple Approach to Troubleshooting High CPU in MySQL

High CPU in MySQL

One of our customers recently asked whether it is possible to identify, from the MySQL side, the query that is causing high CPU usage on his system. The usage of simple OS tools to find the culprit has been a widely used technique for a long time by PostgreSQL and Oracle DBAs, but it […]

Read more

Multi-Threaded Slave Statistics

Multi-Threaded Slave Statistics

In this blog post, I’ll talk about multi-threaded slave statistics printed in MySQL error log file.
MySQL version 5.6 and later allows you to execute replicated events using parallel threads. This feature is called Multi-Threaded Slave (MTS), and to enable it you need to modify the
slave_parallel_workers variable to a value greater than 1.
Recently, a few […]

Read more

MySQL super_read_only Bugs

MySQL Error Code 1215

This blog we describe an issue with MySQL 5.7’s super_read_only feature when used alongside with GTID in chained slave instances.
Background
In MySQL 5.7.5 and onward introduced the gtid_executed table in the MySQL database to store every GTID. This allows slave instances to use the GTID feature regardless whether the binlog option is set or not. Here is […]

Read more