Recently I was doing a little work for a client who has MyISAM tables with many columns (the same one Peter wrote about recently). The client’s performance is suffering in part because of the number of columns, which is over 200. The queries are generally pretty simple (sums of columns), but they’re ad-hoc (can access [...]
XtraDB: The Top 10 enhancements
August 13, 2009 By 5 Comments
Note: This post is part 2 of 4 on building our training workshop. Last week I talked about why you don’t want to shard. This week I’m following up with the top 10 enhancements that XtraDB has over the built-in InnoDB included in MySQL 5.0 and 5.1. Building this list was not really a scientific [...]
Slow DROP TABLE
June 16, 2009 By 21 Comments
It is a known fact that ext3 is not the most efficient file system out there and for example file removals can be painfully slow and cause a lot of random I/O. However, as it turns out, it can sometimes have a much more severe impact on the MySQL performance that it would seem. When [...]
MySQL and IBM
April 6, 2009 By 17 Comments
No, this is not about Sun and IBM This is about MySQL. If you download latest 5.1.33 source code you may find there storage/ibmdb2i directory, which obviously is IBM DB2 related. Interesting that there is no mentioning of new engine in Announcement http://dev.mysql.com/doc/refman/5.1/en/news-5-1-33.html. Quick look into source code says
1 2 3 | MYSQL_STORAGE_ENGINE([ibmdb2i], [], [IBM DB2 for i Storage Engine], [IBM DB2 for i Storage Engine], [max,max-no-ndb]) MYSQL_PLUGIN_DYNAMIC([ibmdb2i], [ha_ibmdb2i.la]) |
Also interesting that license of [...]
Limiting InnoDB Data Dictionary
February 11, 2009 By 13 Comments
One of InnoDB’s features is that memory allocated for internal tables definitions is not limited and may grow indefinitely. You may not notice it if you have an usual application with say 100-1000 tables. But for hosting providers and for user oriented applications ( each user has dedicated database / table) it is disaster. For [...]
High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
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
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 [...]
Living with backups
November 6, 2008 By 28 Comments
Everyone does backups. Usually it’s some nightly batch job that just dumps all MySQL tables into a text file or ordinarily copies the binary files from the data directory to a safe location. Obviously both ways involve much more complex operations than it would seem by my last sentence, but it is not important right [...]
A quest for the full InnoDB status
October 31, 2008 By 4 Comments
When running InnoDB you are able to dig into the engine internals, look at various gauges and counters, see past deadlocks and the list of all open transactions. This is in your reach with one simple command —
1 | SHOW ENGINE InnoDB STATUS |
. On most occasions it works beautifully. The problems appear when you have a large spike in [...]
MySQL Replication vs DRBD Battles
April 28, 2008 By 12 Comments
Well these days we see a lot of post for and against (more, more) using of MySQL and DRBD as a high availability practice. I personally think DRBD has its place but there are far more cases when other techniques would work much better for variety of reasons. First let me start with Florian’s comments [...]
