April 19, 2014

Finding your MySQL High-Availability solution – The questions

After having reviewed the definition my the previous post (The definitions), the next step is to respond to some questions. Do you need MySQL High-Availability? That question is quite obvious but some times, it is skipped. It can also be formulated “What is the downtime cost of the service?”. In the cost, you need to […]

Finding your MySQL High-Availability solution – The definitions

As my first contribution to the MySQL Performance Blog, I joined Percona at the beginning September, I chose to cover the various high-availability (HA) options available for MySQL.  I have done dozen of MySQL HA related engagements while working for Sun/MySQL over the last couple of years using Heartbeat, DRBD and NDB cluster and I’ll […]

3 ways MySQL uses indexes

I often see people confuse different ways MySQL can use indexing, getting wrong ideas on what query performance they should expect. There are 3 main ways how MySQL can use the indexes for query execution, which are not mutually exclusive, in fact some queries will use indexes for all 3 purposes listed here.

High-Performance Click Analysis with MySQL

We have a lot of customers who do click analysis, site analytics, search engine marketing, online advertising, user behavior analysis, and many similar types of work.  The first thing these have in common is that they’re generally some kind of loggable event. The next characteristic of a lot of these systems (real or planned) is […]

How Percona does a MySQL Performance Audit

Our customers or prospective customers often ask us how we do a performance audit (it’s our most popular service). I thought I should write a blog post that will both answer their question, so I can just reply “read all about it at this URL” and share our methodology with readers a little bit. This […]

MySQL extensions for hosting

A few weeks ago I was asked to isolate some functionalities from Mark Callaghan’s MySQL patch bundle. They were extensions adding per-user and per-table accounting to the database, accessible with a new set of commands such as SHOW TABLE_STATISTICS, SHOW INDEX_STATISTICS and SHOW USER_STATISTICS. The first two can interest anyone to periodically check what data […]

Should MySQL Extend GROUP BY Syntax ?

Jan has a good article about finding the row matching some value in the group: This is one illustration of group by limitations in SQL language which is not offset by any MySQL specific extensions,yet As you can see if you want to get one row from the group which is sorted some way you […]

MySQL Installation and upgrade scripts.

I generally find MySQL Sever sufficiently tested, meaning at least minor version upgrades rarely cause the problems. Of course it is not perfect and I remember number of big issues when some releases could not be used due to behavior changes in them and when something had to be rolled back in the next release. […]

Figuring out what limits MySQL Replication

Today I was cloning the master using LVM Snapshot and found it was taking quite a while to catch up, which highlighted replication could be the limiting factor for this system quite soon, so I decided to check what is limiting MySQL Replication speed. My first idea was to check it based on slow query […]

What to tune in MySQL Server after installation

My favorite question during Interview for people to work as MySQL DBAs or be involved with MySQL Performance in some way is to ask them what should be tuned in MySQL Server straight after installation, assuming it was installed with default settings. I’m surprised how many people fail to provide any reasonable answer to this […]