by Peter Zaitsev | Oct 17, 2007 | Percona Events
Yesterday I’ve attended MySQL Customers Conference in London. This event is much smaller size than Users Conference (one day and about 170 people attending) and surely less geeky – there were no one from MySQL Development Support or Consulting teams and...
by Aurimas Mikalauskas | Oct 16, 2007 | Insight for Developers
The other day I had a case with an awful performance of a rather simple join. It was a join on tb1.vid = CONCAT(‘prefix-‘, tb2.id) with tb1.vid – indexed varchar(100) and tb2.id – int(11) column. No matter what I did – forced it to use...
by Peter Zaitsev | Oct 12, 2007 | Insight for DBAs
The question I often get is how far MySQL may fall behind and how to keep replication from lagging. The lag you will see will vary a lot from application to the application and from load to load. Plus what is the most important within same application the lag will...
by Vadim Tkachenko | Oct 12, 2007 | Uncategorized
We many times wrote about InnoDB scalability problems, this time We are faced with one for MyISAM tables. We saw that several times in synthetic benchmarks but never in production, that’s why we did not escalate MyISAM scalability question. This time working on...
by Peter Zaitsev | Oct 11, 2007 | Insight for DBAs
I already wrote about this issue but as I is third team I’m helping customers to resolve this “frm corruption” issue it is the time to return to it again. During MySQL 5.0 release cycle the change was made so now MySQL does not stop if Innodb storage...
by Peter Zaitsev | Oct 6, 2007 | Percona Events
Almost two weeks have passed since HighLoad 2007 conference in Moscow, Russia so I’m pretty late with feedback and my only excuse I was pretty busy to spare some time for it. Lets start with bright side. The conference had a lot of great sessions by experts in...
by Peter Zaitsev | Oct 5, 2007 | Benchmarks, Insight for Developers
When I was comparing performance of UNION vs MySQL 5.0 index merge algorithm Sinisa pointed out I should be using UNION ALL instead of simple UNION in my benchmarks, and he was right. Numbers would be different but it should not change general point of having...
by Peter Zaitsev | Oct 5, 2007 | Percona Events
About one month ago we posted a call for interns to work with us on various MySQL Performance related things. We got good number of replies and a lot of people wondered what tasks exactly we could offer as surely this sort of involvement should be fun and should teach...
by Peter Zaitsev | Oct 4, 2007 | Insight for DBAs
Recent couple of days our team was pointed to number of bugs in MySQL 5.0 which again seriously shakes the confidence in both MySQL Quality Control and bug fix promptness. Let me just take couple of bugs as examples: Triggers broken with auto-increment columns for...
by Peter Zaitsev | Sep 28, 2007 | Insight for Developers
Have you ever had a question about Innodb internal design or behavior which is not well covered in MySQL manual ? I surely had. Now you have a great chance to have them answered ! Heikki Tuuri, Creator of Innodb will answer your Questions about Innodb at MySQL...
by Peter Zaitsev | Sep 28, 2007 | Insight for Developers
Many Open Source software solutions use database per user (or set of tables per user) which starts to cause problems if it is used on massive scale (blog hosting, forum hosting etc), resulting of hundreds of thousands if not millions of tables per server which can...
by Peter Zaitsev | Sep 28, 2007 | Insight for DBAs
It always surprised me how little Innodb team seems to think about product usability/ease of use, when it comes to settings, performance management etc. I could understand many things 5 years ago, like a lot of information being available only in hard to parse SHOW...
by Vadim Tkachenko | Sep 26, 2007 | Insight for DBAs
There was long played scalability issue with InnoDB auto-increment field. For details check Bug 16979. In short words the problem is in case of insert into table with auto-increment column the special AUTO_INC table level lock is obtained, instead of usual row-level...
by Peter Zaitsev | Sep 18, 2007 | Percona Events
26th of September, just after HighLoad conference I will have full day MySQL master class. This time we will talk about Innodb Architecture and Performance Optimization and when will discuss some MySQL Performance Optimization and Scaling case studies from audience...
by Peter Zaitsev | Sep 18, 2007 | Insight for Developers
Every so often you need to perform sort results retrieved from MySQL when your WHERE clause goes beyound col=const values which would allow MySQL to still use second portion of the index for the order by. Ranges as well as IN lists make this optimization impossible,...
by Peter Zaitsev | Sep 17, 2007 | Benchmarks, Insight for Developers
Quite typical query for reporting applications is to find top X values. If you analyze Web Site logs you would look at most popular web pages or search engine keywords which bring you most of the traffic. If you’re looking at ecommerce reporting you may be...
by Peter Zaitsev | Sep 17, 2007 | Benchmarks, Insight for DBAs
The more I work with MySQL Performance Optimization and Optimization for other applications the better I understand I have to less believe in common sense or common sense of documentation writers and do more benchmarks and performance research. I just recently wrote...
by Peter Zaitsev | Sep 15, 2007 | Percona Events
I finally got my visa so I’m going to MySQL Developers meeting in Heidelberg, Germany next week. Hopefully it will be great source of “technical insight” information, either from organized sessions or from developers themselves. Plus I’m...
by Peter Zaitsev | Sep 13, 2007 | Insight for DBAs
General query logging can be very handy in MySQL on profuction server for various debugging needs. Unfortunately you can’t switch it on and off without restarting server until MySQL 5.0. What can you do in MySQL 5.0 and below ? Use Our Patch – With this...
by Vadim Tkachenko | Sep 13, 2007 | Insight for DBAs
If you like to compile MySQL from sources by yourself, for different needs, like debugging, testing etc, you probably can face this issue. What I usually do to fast compile and test is ./configure --prefix=/dir/to/mysql make make install 123 ./configure...
