Troubleshooting crashes is never a fun task, especially if MySQL does not report the cause of the crash. For example, when MySQL runs out of memory. Peter Zaitsev wrote a blog post in 2012: Troubleshooting MySQL Memory Usage with a lots of useful tips. With the new versions of MySQL (5.7+) and performance_schema we have the ability to troubleshoot MySQL memory allocation much more easily.

In this blog post I will show you how to use it.

First of all, there are 3 major cases when MySQL will crash due to running out of memory:

1. MySQL tries to allocate more memory than available because we specifically told it to do so. For example: you did not set innodb_buffer_pool_size correctly. This is very easy to fix
2. There is some other process(es) on the server that allocates RAM. It can be the application …

Please join Percona’s Principal Support Engineer, Sveta Smirnova, as she presents “Basic Internal Troubleshooting Tools for MySQL Server” on Thursday, February 15, 2018, at 10:00 am PST (UTC-8) / 1:00 pm EST (UTC-5).

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MySQL Server has many built-in troubleshooting tools. They are always available and can provide many insights on what is happening internally. Many graphical tools, such as Percona Monitoring and Management …

MySQL databases are great work horses of the internet.  They back tons of modern websites, from blogs and checkout carts, to huge sites like Facebook.  But these technologies don't run themselves.  When you're faced with a system that is slowing down, you'll need the right tools to diagnose and troubleshoot the problem.  MySQL has a huge community following and that means scores of great tools for your toolbox. Here are 7 ways to troubleshoot MySQL.

1. Use innotop

Innotop is a great tool for MySQL which despite the name monitors MySQL generally as well as InnoDB usage.  It's fairly easy to install, just download the perl script. Be sure to include a [client] section to your local users .my.cnf file (you have one don't you?).  Inside that section, place one line with "user=xyz" and one line with "password=abc".

If you're concerned that installing something new is too …