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 key, forced a different join order, it did not […]Read more
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 the customer system we figured out that box with 1 CPU […]Read more
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 engine failed to initialize but starts properly… […]
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 their field. A lot of top […]
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 optimization of moving […]Read more
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 you something.
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 Innodb tables (bug 26316). As […]
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 Performance Blog.
Please leave your questions […]
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 become really inefficient.
It is especially inefficient with […]