by Baron Schwartz | Sep 24, 2008 | Insight for Developers
A paginated display is one of the top optimization scenarios we see in the real world. Search results pages, leaderboards, and most-popular lists are good examples. You know the design pattern: display 20 results in some most-relevant order. Show a “next”...
by Peter Zaitsev | Sep 22, 2008 | Insight for DBAs
The problem of MySQL Replication unable to catch up is quite common in MySQL world and in fact I already wrote about it. There are many aspects of managing mysql replication lag such as using proper hardware and configuring it properly. In this post I will just look...
by Ewen Fortune | Sep 22, 2008 | Percona Software
Whilst working with a client recently I noticed a large number of temporary tables being created on disk. show global status like 'Created_tmp%' | Created_tmp_disk_tables | 91970 | | Created_tmp_files | 19624 | | Created_tmp_tables | 1617031 | 12345 show global status...
by Peter Zaitsev | Sep 21, 2008 | Percona Events
I’ll be speaking at HighLoad++ conference in Moscow,Russia taking place 6,7 Oct 2008. This conference was quite success with very interesting presentation last year and I’m hoping it would be even better this year. I also will have a full dayMaster Class...
by Baron Schwartz | Sep 20, 2008 | Insight for Developers
When optimizing queries for customers, the first thing I do with a slow query is figure out what it’s trying to do. You can’t fully optimize a query unless you know how to consider alternative ways to write it, and you can’t do that unless you know...
by Peter Zaitsev | Sep 16, 2008 | Insight for DBAs
Quite commonly I get a question similar to this – “My Innodb Buffer Pool is already 90% full, should I be thinking about upgrading memory already?” This is a wrong way to put the question. Unless you have very small database (read as database which...
by Vadim Tkachenko | Sep 12, 2008 | Percona Software
Usually unused indexes are devil, they waste diskspace, cache, they make INSERT / DELETE / UPDATE operations slower and what makes them worse – it is hard to find them. But now ( with userstatsV2.patch) you can find all unused indexes (since last restart of...
by Vadim Tkachenko | Sep 12, 2008 | Percona Software
Recently Google published V2 release of patches, one of them user_statistics we use in our releases. New features are quite interesting so we decided to port it to fresh releases of MySQL. Features includes: New statistics per user (Cpu_time, Bytes_received,...
by Peter Zaitsev | Sep 12, 2008 | Insight for DBAs
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...
by Peter Zaitsev | Sep 11, 2008 | Insight for DBAs
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...
by Peter Zaitsev | Sep 11, 2008 | Insight for DBAs
Take a look at this: mysql> repair table a3; +---------+--------+----------+----------+ | Table | Op | Msg_type | Msg_text | +---------+--------+----------+----------+ | test.a3 | repair | status | OK | +---------+--------+----------+----------+ 1 row in set (0.10...
by Vadim Tkachenko | Sep 9, 2008 | Benchmarks, Percona Software
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) The workload emulates...
by Vadim Tkachenko | Sep 8, 2008 | Percona Software
We gathered together our ideas of MySQL improvements on this page https://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...
by Vadim Tkachenko | Sep 5, 2008 | Percona Software
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...
by Peter Zaitsev | Sep 4, 2008 | Percona Events
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...
by Peter Zaitsev | Sep 3, 2008 | Insight for DBAs
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...
by Peter Zaitsev | Sep 2, 2008 | Insight for DBAs
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...
by Peter Zaitsev | Sep 1, 2008 | Insight for DBAs
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...
by Baron Schwartz | Aug 23, 2008 | Insight for DBAs
Yesterday I helped someone who was seeing a lot of “server has gone away” error messages on his website. While investigating this problem, I noticed several things amiss, which appeared to be related but really weren’t. The biggest measurable sign...
by Peter Zaitsev | Aug 22, 2008 | Percona Events
We’ve discussed today how we should implement MySQL Version advisory in mk-audit tool. One obvious questions was to look at the end of life – it is often bad idea to run MySQL versions past end of life as even security bugs may not be fixed in these...
