A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single row. Today I wanted to look a bit deeper into the problem, which I also filed as a bug. First […]
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Thanks to all who attended my webinar yesterday. The slides and recording are available on the webinar’s page. I was a bit overwhelmed with the amount of questions that came in and I’ll try to answer them the best I can here. Q: Does Percona XtraDB Cluster support writing to multiple master? Yes, it does. However, […]
Thanks to everyone who was in attendance on 05 June 2013 for my “Choosing a MySQL HA Solution” webinar. If you weren’t able to make it but are interested in listening to the presentation, it’s currently up and available for viewing over at percona.com. My apologies if we weren’t able to get to your question […]
The MySQL optimizer makes the decision of what execution plan to use based on the information provided by the storage engines. That information is not accurate in some engines like InnoDB and they are based in statistics calculations therefore sometimes some tune is needed. In InnoDB these statistics are calculated automatically, check the following blog […]
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! Whatâ€™s the “ideal” use case for the PBXT engine, and how does it compare in performance? Â When would I […]
I have written before – MyISAM Does Not Scale, or it does quite well – two main things stopping you is table locks and global mutex on the KeyCache. Table Locks are not the issue for Read Only workload and write intensive workloads can be dealt with by using with many tables but Key Cache […]
As you might know ANALYZE TABLE just quickly updates table statistics using index dives, unlike with MyISAM when it scans indexes holding table lock for long period of time. So ANALYZE TABLE should be very fast and non intrusive operation doing just little update on the data. Right ?
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 […]
I’ve just been pointed to the nice tool which I was waiting for years to see. It is fincore – little perl script which allows you to see what pages of file are cached in OS memory. This is really cool.
Reading last few days worth of planet MySQL and commenting on some entries as you can see. The post by Oli catches my attention. There is also PDF with more details available Oli is saying you can use MySQL with Active Active Clustering and MyISAM tables if you follow certain rules like enabling external locking, […]