… see “VSZ” going down. What you might see instead…mysql> select sum(data_length+index_length) from information_schema.tables where engine=’memory… and there are “swap outs” but a lot less “…MySQL Support contract can be handy. Conclusion Understanding where MySQL can allocate memory can help us to find…
Comment: Introducing new type of benchmark
February 25, 2012 By 16 Comments
…final question, I definitely find this useful. Benchmarks are written to provide the… stream developers are tuning their engines towards them (which is not what they’re there for.) …replacements for MySQL like Percona and MariaDB which are either tweaking or flat out overhauling their query engines …
Post: Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
May 3, 2011 By 13 Comments
…-implementing storage engine, is to get rid of–purge–the old versions of the records as they become obsolete. In MySQL 5… 5.5 yet. Let’s test these two implementations and find out what benefits, if any, do the additional purge threads bring. The… to not to penalize further TPS. MySQL 5.6.2 Results Now let’s test MySQL 5.6.2. It is important…
Post: MySQL opening .frm even when table is in table definition cache
November 21, 2011 By 8 Comments
… enough, spin-offs from this work included being able to find out and then test that the ENUM limit of 65,535… how the Storage Engine API is called. But back to what the above strace shows. In MySQL 5.5 you can find in sql…_TYPE. i.e. what storage engine it is. We can ignore the upper limit on number of storage engines for MySQL and understanding the…
Post: How (not) to find unused indexes
October 16, 2009 By 2 Comments
… to be able to find any indexes that have low cardinality, in an effort to find out what indexes should be removed…DEFAULT ”, PRIMARY KEY (`Code`), KEY `Population` (`Population`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; mysql> SELECT count(*) FROM Country; +———-+ | count(*) | +———-+ |Â Â…
Post: INFORMATION_SCHEMA tables in the InnoDB pluggable storage engine
May 24, 2008 By Leave a Comment
… been written about the new InnoDB pluggable storage engine, which Innobase released at the MySQL conference last month. We’ve written posts… to add. (I subsequently discovered that it is possible to find out more information on InnoDB locks even in the older versions… with extensive examples of how to use them to find out what is blocking what and so on. Note that the InnoDB plugin manual…
Post: Testing MySQL column stores
August 16, 2010 By 15 Comments
…experience developing such cases for MySQL column-based storage engines in the past. …find significant defects in Infobright that would be “show stoppers” for typical OLAP analysis queries. These tests were intended to approximate what…. I did not change any “out of the box” settings for Infobright…
Post: High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
… click analysis, site analytics, search engine marketing, online advertising, user behavior … to go together. Figure out what other types of data you’… your application in advance. What about partitioning in MySQL 5.1? …column record only blue clicks; to find out non-blue clicks you subtract one…
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
… error logs allows you to figure out what is the problem 070223 13:26:01InnoDB: Warning: cannot find a free slot for an… active transactions running concurrently? I hope with pluggable storage engine interface Sun/MySQL spends some time to make things consistent. There should… perror to find out this error is foreign key related but you also need to run SHOW INNODB STATUS to see what exactly…
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
… buffers. Watch for these especially now with many storage engines being released for MySQL by various parties. I do not pretend this… memory consumers out where and trying to find peak possible usage for each is impractical – so my advice would be measure what you get in practice and how memory consumption reacts to changing various variables. For example you may find out increasing…
