May 19, 2013

Using MySQL Sandbox with Percona Server

One of the most useful tools if you’re working with multiple versions of MySQL Servers is MySQL Sandbox which allows you to maintain many different versions of MySQL, Percona Server, MariaDB. If you’re just working with single sandbox you can just use MySQL Sandbox in its most basic way and it will work:

However [...]

Sphinx search performance optimization: multi-threaded search

Queries in MySQL, Sphinx and many other database or search engines are typically single-threaded. That is when you issue a single query on your brand new r910 with 32 CPU cores and 16 disks, the maximum that is going to be used to process this query at any given point is 1 CPU core and [...]

MySQL Wish for 2013 – Better Memory Accounting

With Performance Schema improvements in MySQL 5.6 I think we’re in the good shape with insight on what is causing performance bottlenecks as well as where CPU resources are spent. (Performance Schema does not accounts CPU usage directly but it is something which can be relatively easily derived from wait and stage information). Where we’re [...]

Edge-case behavior of INSERT…ODKU

A few weeks back, I was working on a customer issue wherein they were observing database performance that dropped through the floor (to the point of an outage) roughly every 4 weeks or so. Nothing special about the environment, the hardware, or the queries; really, the majority of the database was a single table with [...]

Distro Packages, Pre-built Binaries or Compile Your Own MySQL

I’ve been helping customers deploy and maintain MySQL (and variants) for the last couple of years and it has always been interesting to hear customer thoughts on how they want their servers installed. It has also been asked many times not only by our support and consulting customers, but widely from different forums and blogs [...]

Percona XtraDB Cluster: Failure Scenarios with only 2 nodes

During the design period of a new cluster, it is always advised to have at least 3 nodes (this is the case with PXC but it’s also the same with PRM). But why and what are the risks ? The goal of having more than 2 nodes, in fact an odd number is recommended in [...]

New variable slave_max_allowed_packet for slave servers

One month ago I wrote about how a big read_buffer_size could break the replication. The bug is not solved but now there is an official workaround to ease this problem using a new configuration variable: slave_max_allowed_packet This new variable will be available in 5.1.64, 5.5.26, and 5.6.6 and can establish a different limit on the [...]

MySQL Upgrade Webinar Questions Followup

I did a Webinar about MySQL Upgrade – Best Practices Yesterday and there were some questions we could not answer during Webinar, following Jay’s Lead I decided to post them as a Blog Post. Q: Can you go directly MySQL 5.0 to 5.5 for MyISAM tables? MyISAM have not been getting any significant development since [...]

ALTER TABLE: Creating Index by Sort and Buffer Pool Size

Today I was looking at the ALTER TABLE performance with fast index creation and without it with different buffer pool sizes. Results are pretty interesting. I used modified Sysbench table for these tests because original table as initially created only has index on column K which initially contains only zeros, which means index is very [...]

DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL

Suppose you have turned on innodb_file_per_table (which means that each table has its own tablespace), and you have to drop tables in a background every hour or every day. If its once every day then you can probably schedule the table dropping process to run during off-peak hours. But I have seen cases where the [...]