September 2, 2014

What Bugs makes you to recomend upgrade most frequently ?

What bug makes you to recommend upgrading most frequently ? For me it is this bug which makes it quite painful to automate various replication tasks. It is not the most critical bug by far but this makes it worse – critical bugs would usually cause upgrades already or were worked around while such stuff […]

AUTO_INCREMENT and MERGE TABLES

How would you expect AUTO_INCREMENT to work with MERGE tables ? Assuming INSERT_METHOD=LAST is used I would expect it to work same as in case insertion happens to the last table… which does not seems to be the case. Alternatively I would expect AUTO_INCREMENT to be based off the maximum value across all tables, respecting […]

Can you Trust CHECK TABLE ?

Take a look at this:

The sort order is obviously wrong while CHECK TABLE is not reporting any error

The performance effects of new patches

We are going to show the effects of the new patches applied to Percona HighPerf release. As you see from the following graphs, there is significant difference to normal version when the data bigger than buffer pool (right graph shows CPU usage)

Development plans

We gathered together our ideas of MySQL improvements on this page http://www.percona.com/percona-lab/dev-plan.html and we are going to implement some of them. My favorite one is – make InnoDB files .ibd (one created with –innodb-file-per-table=1) movable from one server to another, however it is sort of challenging. Probably next one patch we want to integrate is […]

New patches, new builds

We made new patches, improved previous and want to announce new builds for 5.0.62, 5.0.67 and 5.1.26 versions. One of biggest changes we separated releases of 5.0 into two branches. First, just “-percona” release is more stable and contains only stable and proven on many installation patches. Second is “-percona-highperf” release, which contains experimental patches […]

How quickly you should expect to see bugs fixed

Over a year ago I wrote about pretty nasty Innodb Recovery Bug. I ran in the same situation again (different system, different customer) and went to see the status of the bug… and it is still open. You may thing it is minor issue but in fact with large buffer pool this bug makes database […]

ANALYZE: MyISAM vs Innodb

Following up on my Previous Post I decided to do little test to see how accurate stats we can get for for Index Stats created by ANALYZE TABLE for MyISAM and Innodb. But before we go into that I wanted to highlight about using ANALYZE TABLE in production as some people seems to be thinking […]

Beware of running ANALYZE in Production

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 ?

How network can impact MySQL Operations ?

This week I’ve worked with the customer doing certain work during maintenance window which involved a lot of data copying around between MySQL boxes. We had prepared well and had measured how fast we could copy the data between servers of these kind connected to the same network, and we did the same thing before. […]