You might know if you have long running transactions you’re risking having a lot of “garbage” accumulated in undo segment size which can cause performance degradation as well as increased disk space usage. Long transactions can also be bad for other reasons such as taking row level locks which will prevent other transactions for execution, [...]
Percona Server 5.1.50-rel12.1
October 14, 2010 By 2 Comments
Dear Community, Percona Server version 5.1.50-rel12.1 RC is now available for download. Functionality Added or Changed Percona Server 5.1.50-rel12.1 is now based on MySQL 5.1.50. New Features Added: innodb_lru_dump_restore – Implemented automatic dumping of the buffer pool at specified intervals. innodb_buffer_pool_shm – Implemented option ”innodb_buffer_pool_shm_checksum”; when enabled, shared memory buffer pool is checksum validated. This [...]
Recover BLOB fields
July 1, 2010 By 4 Comments
For a long time long types like BLOB, TEXT were not supported by Percona InnoDB Recovery Tool. The reason consists in a special way InnoDB stores BLOBs. An InnoDB table is stored in a clustered index called PRIMARY. It must exist even if a user hasn’t defined the primary index. The PRIMARY index pages are [...]
When should you store serialized objects in the database?
January 21, 2010 By 47 Comments
A while back Friendfeed posted a blog post explaining how they changed from storing data in MySQL columns to serializing data and just storing it inside TEXT/BLOB columns. It seems that since then, the technique has gotten more popular with Ruby gems now around to do this for you automatically.
How number of columns affects performance ?
September 28, 2009 By 11 Comments
It is pretty understood the tables which have long rows tend to be slower than tables with short rows. I was interested to check if the row length is the only thing what matters or if number of columns we have to work with also have an important role. I was interested in peak row [...]
Friday challenge: ibd recovery
May 15, 2009 By 8 Comments
I want to make this Friday a bit more interesting – how do you feel to train a bit in InnoDB data recovery techniques. I have .ibd datafile which was created by query CREATE TABLE `tryme` ( `email` mediumblob, `content` mediumblob ) ENGINE=InnoDB … (SOME PARAMETERS SKIPPED) …; and I inserted one record into this [...]
Should you move from MyISAM to Innodb ?
January 12, 2009 By 59 Comments
There is significant portion of customers which are still using MyISAM when they come to us, so one of the big questions is when it is feasible to move to Innodb and when staying on MyISAM is preferred ? I generally prefer to see Innodb as the main storage engine because it makes life much [...]
Quickly preloading Innodb tables in the buffer pool
May 1, 2008 By 9 Comments
In the previous post I mentioned a way I use to preload Clustered Index (data) for Innodb tables. Though I thought this topic would benefit from a bit more information. But lest first start with feature request for Innodb Team: All ways I mention here are hacks and they can’t be as efficient as native [...]
Real-Life Use Case for “Barracuda” InnoDB File Format
April 23, 2008 By 11 Comments
In one of his recent posts Vadim already gave some information about possible benefits from using new InnoDB file format but in this post I’d like to share some real-life example how compression in InnoDB plugin could be useful for large warehousing tasks.
State of MySQL Market and will Replication live ?
April 9, 2008 By 29 Comments
There are interesting posts these day about future of MySQL Replication by Brian Frank and Arjen. I think it very interesting to take a look at a bit bigger picture using framework from Innovators Dilemma and Innovators Solution. I’m not going to speak about disruption and commoditisation of Database Market, leaving this for Market talks, [...]
