Search Results for: clear mysql log file

Profiling MySQL queries from Performance Schema

When optimizing queries and investigating performance issues, MySQL comes with built in support for profiling queries aka SET profiling = 1; . This is already awesome and simple to use, but why the PERFORMANCE_SCHEMA alternative? Because profiling will be removed soon (already deprecated on MySQL 5.6 ad 5.7); the built-in profiling capability can only be enabled per session. This […]

The future of MySQL quality assurance: Introducing pquery

Being a QA Engineer, how would you feel if you had access to a framework which can generate 80+ crashes – a mix of hitting developer introduced assertions (situations that should not happen), and serious unforeseen binary crashes – for the world’s most popular open source database software – each and ever hour? What if you could […]

Using Percona Cloud Tools to solve real-world MySQL problems

For months when speaking with customers I have been positioning Percona Cloud Tools (PCT) as a valuable tool for the DBA/Developer/SysAdmin but only recently have I truly been able to harness the data and make a technical recommendation to a customer that I feel would have been very difficult to accomplish otherwise. Let me provide […]

Getting mutex information from MySQL’s performance_schema

We have been using SHOW ENGINE INNODB MUTEX command for years. It shows us mutex and rw-lock information that could be useful during service troubleshooting in case of performance problems. As Morgan Tocker announced in his blog post the command will be removed from MySQL 5.7 and we have to use performance_schema to get that […]

What happens when your application cannot open yet another connection to MySQL

Have you ever experienced a situation where one moment you can connect to the MySQL database and the next moment  you cannot, only to be able to connect again a second later? As you may know one cannot open infinite connections with MySQL. There’s a practical limit and more often than not it is imposed […]

(More) Secure local passwords in MySQL 5.6 and up

I log into a lot of different servers running MySQL and one of the first things I do is create a file in my home directory called ‘.my.cnf’ with my credentials to that local mysql instance:

This means I don’t have to type my password in every time, nor am I tempted to include […]

A closer look at the MySQL ibdata1 disk space issue and big tables

A recurring and very common customer issue seen here at the Percona Support team involves how to make the ibdata1 file “shrink” within MySQL. I can only imagine there’s a degree of regret by some of the InnoDB architects on their design decisions regarding disk-space management by the shared tablespace* because this has been a big […]

Managing shards of MySQL databases with MySQL Fabric

This is the fourth post in our MySQL Fabric series. In case you’re joining us now, we started with an introductory post, and then discussed High Availability (HA) using MySQL Fabric here (Part 1) and here (Part 2). Today we will talk about how MySQL Fabric can help you scale out MySQL databases with sharding. Introduction At the […]

Failover with the MySQL Utilities – Part 1: mysqlrpladmin

MySQL Utilities are a set of tools provided by Oracle to perform many kinds of administrative tasks. When GTID-replication is enabled, 2 tools can be used for slave promotion: mysqlrpladmin and mysqlfailover. We will review mysqlrpladmin (version 1.4.3) in this post. Summary mysqlrpladmin can perform manual failover/switchover when GTID-replication is enabled. You need to have […]