Following on from our earlier announcement, Paul McCullagh has responded with the answers to your questions – as well as a few I gathered from other Percona folks, and attendees of OpenSQL Camp. Thank you Paul! What’s the “ideal” use case for the PBXT engine, and how does it compare in performance?  When would I [...]
Air traffic queries in InfiniDB: early alpha
November 2, 2009 By 19 Comments
As Calpont announced availability of InfiniDB I surely couldn’t miss a chance to compare it with previously tested databases in the same environment. See my previous posts on this topic: Analyzing air traffic performance with InfoBright and MonetDB Air traffic queries in LucidDB I could not run all queries against InfiniDB and I met some [...]
Just do the math!
July 6, 2009 By 4 Comments
One of the most typical reasons for performance and scalability problems I encounter is simply failing to do the math. And these are typically bad one because it often leads to implementing architectures which are not up for job they are intended to solve. Let me start with example to make it clear. Lets say [...]
Talking MySQL to Sphinx
April 19, 2009 By 4 Comments
In the recently released Sphinx version 0.9.9-rc2 there is a support for MySQL wire protocol and SphinxQL – SQL-like language to query Sphinx indexes. This support is currently in its early preview stage but it is still fun to play with. A thing to mention – unlike MySQL Storage Engines, some of which as InfoBright [...]
How much memory can MySQL use in the worst case?
February 12, 2009 By 17 Comments
I vaguely recall a couple of blog posts recently asking something like “what’s the formula to compute mysqld’s worst-case maximum memory usage?” Various formulas are in wide use, but none of them is fully correct. Here’s why: you can’t write an equation for it.
How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
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 [...]
10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
People are sometimes contacting me and asking about bugs like this which provide a trivial way to crash MySQL to the user with basic privileges and asking me what to do. My answer to them is – there is nothing new to it and they just sit should back and relax Really – there are [...]
InnoDB in self-compiled MySQL 5.1
September 13, 2007 By 9 Comments
If you like to compile MySQL from sources by yourself, for different needs, like debugging, testing etc, you probably can face this issue. What I usually do to fast compile and test is
1 2 3 | ./configure --prefix=/dir/to/mysql make make install |
and then, for example, load the dump of InnoDB from previous version:
1 | mysql testdatabase < dump.sql |
I bet you will not notice all your [...]
How much overhead is caused by on disk temporary tables
August 16, 2007 By 26 Comments
As you might know while running GROUP BY and some other kinds of queries MySQL needs to create temporary tables, which can be created in memory, using MEMORY storage engine or can be created on disk as MYISAM tables. Which one will be used depends on the allowed tmp_table_size and also by the data which [...]
TMP_TABLE_SIZE and MAX_HEAP_TABLE_SIZE
January 19, 2007 By 17 Comments
We all know disk based temporary tables are bad and you should try to have implicit temporary tables created in memory where possible, do to it you should increase tmp_table_size to appropriate value and avoid using blob/text columns which force table creation on the disk because MEMORY storage engine does not support them Right ? [...]
