Today’s blog post diving into the waters of the MySQL buffer pool is a cross-post from Groupon’s engineering blog, and is Part 1 of 2. Thank you to Kyle Oppenheim at Groupon for contributing to this project and post. We’ll be posting Part 2 on Thursday. I’ll be at the Percona Live MySQL Conference and [...]
Percona Toolkit Webinar followup Q&A
December 19, 2012 By 1 Comment
First, a thank you to everyone who attended the webinar Today, I appreciate your time and nice comments. As promised, here are answers to questions that couldn’t be answered during the talk: Q: How do you install the tools? The manual has full details, but it’s important to know that the latest release for [...]
Get Me Some Query Logs!
November 22, 2012 By 14 Comments
One of my favorite tools in the Percona Toolkit is pt-query-digest. This tool is indispensable for identifying your top SQL queries, and analyzing which queries are accounting for your database load. But the report you get from pt-query-digest is only as good as the log of queries you give it as input. You need a large [...]
Replaying database load with Percona Playback
October 25, 2012 By 9 Comments
If you are planning to upgrade or make any configuration change on your MySQL database the first advice usually is: – Benchmark! How should we do that benchmark? People usually run generic benchmark tools like sysbench, tpcc or mysqlslap that are good to know the number of transactions per seconds that a database can do [...]
Find unused indexes
June 30, 2012 By Leave a Comment
I wrote one week ago about how to find duplicate indexes. This time we’ll learn how to find unused indexes to continue improving our schema and the overall performance. There are different possibilites and we’ll explore the two most common here. User Statistics from Percona Server and pt-index-usage. User Statistics User Statistics is an improvement [...]
How To Test Your Upgrades – pt-upgrade
December 29, 2011 By 7 Comments
Upgrades are usually one of the biggest part of any database infrastructure maintenance. Even with enough planning something else can go bad after sending your production application to the version you’ve upgraded to. Let’s look at how one Percona Toolkit tool, pt-upgrade can help you identify what to expect and test your upgrades better which [...]
Percona-XtraDB-9.1: released and new coming features
March 17, 2010 By 14 Comments
Recently Alexandr announced new Percona-XtraDB-9.1 release, and now it is good time to summarize features we have and what is expected soon. This release contains long waited features from 5.0: extended slow.log USER/TABLE/INDEX/CLIENT_STATISTICS + THREAD_STATISTICS ( coming in release-10) Extended slow.log is now even more extended, there is additional information for each query:
1 | # Bytes_sent: 4973 Tmp_tables: 1 Tmp_disk_tables: 1 Tmp_table_sizes: 7808 |
That [...]
Introducing percona-patches for 5.1
February 9, 2010 By 21 Comments
Our patches for 5.0 have attracted significant interest. You can read about SecondLife’s experience here, as well as what Flickr had to say on their blog. The main improvements come in both performance gains and improvements to diagnostics (such as the improvements to the slow log output, and INDEX_STATISTICS). Despite having many requests to port [...]
InnoDB: look after fragmentation
November 5, 2009 By 12 Comments
One problem made me puzzled for couple hours, but it was really interesting to figure out what’s going on. So let me introduce problem at first. The table is
1 2 3 4 5 6 7 8 | CREATE TABLE `c` ( `tracker_id` int(10) unsigned NOT NULL, `username` char(20) character set latin1 collate latin1_bin NOT NULL, `time_id` date NOT NULL, `block_id` int(10) unsigned default NULL, PRIMARY KEY (`tracker_id`,`username`,`time_id`), KEY `block_id` (`block_id`) ) ENGINE=InnoDB |
Table has 11864696 rows and takes Data_length: 698,351,616 bytes on disk The problem is that after restoring table from mysqldump, the query that scans data [...]
How to generate per-database traffic statistics using mk-query-digest
September 16, 2009 By Leave a Comment
We often encounter customers who have partitioned their applications among a number of databases within the same instance of MySQL (think application service providers who have a separate database per customer organization … or wordpress-mu type of apps). For example, take the following single MySQL instance with multiple (identical) databases:
