Jun 30, 2006 |
Hardware and Storage
This post is not exactly about MySQL Performance or about Performance at all, but I guess it should be interested to many MySQL DBAs and other people involved running MySQL In production. Recently I’ve been involved in troubleshooting Dell Poweredge 2850 system running RAID5 using 6GB internal hard drives, which give about 1.4TB of usable […]
Jun 29, 2006 |
Insight for DBAs
“What cache hit rate is good for optimal MySQL Performance” is typical question I’m asked. It could by MyISAM key_buffer or Innodb innodb_buffer_pool it does not really matter. In both cases trying to come up with constant “good” hit rate is looking for trouble. Well of course you can name 100% hit rate and all […]
Jun 26, 2006 |
Insight for DBAs
As we know build in full text search is currently limited only to MyISAM search engine as well as has few other limits. Today Sphinx Search plugin for MySQL was released which now provides fast and easy to use full text search solution for all storage engines. This version also adds a lot of other […]
Jun 23, 2006 |
Benchmarks, Insight for DBAs
I frequently get questions along the lines of “how many transactions per second MySQL can do” or “how many servers I need to handle 100.000 users” or “which hardware would be enough to handle my 40GB” database. There are two things which are very interesting about these questions which make them funny and annoying at […]
Jun 17, 2006 |
Insight for DBAs
There were recently number of posts about MyISAM, for example Arjen wrote pretty nice article about MyISAM features so I thought I would share my own view on using MyISAM in production. For me it is not only about table locks. Table locks is only one of MyISAM limitations you need to consider using it […]
Jun 09, 2006 |
Insight for DBAs, MySQL
If you’ve been reading enough database-related forums, mailing lists, or blogs you have probably heard complains about MySQL being unable to handle more than 1,000,000 (or select any other number) rows by some of the users. On the other hand, it is well known with customers like Google, Yahoo, LiveJournal, and Technorati, MySQL has installations […]
Jun 08, 2006 |
Insight for DBAs
MySQL Server has tons of variables which may be adjusted to change behavior or for performance purposes. They are documented in the manual as well as on new page Jay has created. Still I see constant confusion out where which of variables apply to storage engines only and which are used on SQL layer and […]
Jun 08, 2006 |
Benchmarks
AnandTech published Intel Woodcrest preview benchmarks which have some numbers for MySQL as well. From these numbers performance looks great and it looks like finally Intel has something to respond to AMD Opterons on Server market. Now competition heats up and we’ll see what AMD will have to respond. As Opteron did not have serious […]
Jun 06, 2006 |
Sometimes I see people thinking about buffers as “larger is always better” so if “large” MySQL sample configuration is designed for 2GB and they happen to have 16, they would simply multiply all/most values by 10 and hope it will work well. Obviously it does not. The least problem would be wasting memory, allocating a […]
May 29, 2006 |
Benchmarks
We had discussion today which involved benchmarks of Join speed for MyISAM and Innodb storage engines for CPU bound workload, this is when data size is small enough to fit in memory and so buffer pool. I tested very simple table, having with about 20.000 rows in it on 32bit Linux. The columns “id” “i” […]
May 29, 2006 |
Insight for DBAs
MySQL INSERT ON DUPLICATE KEY UPDATE is very powerful but often forgotten MySQL feature. It was introduced in MySQL 4.1 but I still constantly see people unaware of it. Myself I like this feature big deal because it is designed in truly MySQL style – very efficient solution for frequent task while keeping it beautiful […]
May 27, 2006 |
Benchmarks
Sun has now published SpecJAppServer2004 benchmark results with MySQL. The results are pretty good as we can see and it is also good to know some room for tuning remains so we can hope getting even better results this time. Jenny Chen published good MySQL Tuning writeup so I would not repeat it. It was […]
May 27, 2006 |
Insight for DBAs
Jeremy Cole recently posted very nice post about MySQL Replication Performance. There are however few points I should comment on. Jeremy Speaks about MyISAM and Innodb in the same terms, in fact they are quite different for Replication. As you probably know MyISAM uses buffered IO so if master crashes you’re out of sync anyway […]
May 22, 2006 |
Insight for Developers
In connection to my previous post I was thinking how Web 2.0 with its massive use of Web Services affect LAMP Stack ? Well actually there are serious difference both for client and server application development which you might want to take into account. If you’re developing Web Service Server application you will most likely […]
May 21, 2006 |
Insight for Developers
Apache Web server could frequently be bottleneck for your LAMP stack, or you might be wasting resources on your web servers. The problem with Apache server comes from “client per process” architecture which you have to stick to at least for dynamic content served by PHP or ModPerl. With “client per process” you end up […]
May 17, 2006 |
Insight for DBAs
Every so often people ask me the question how should they estimate memory consumption by MySQL Server in given configuration. What is the formula they could use. The reasons to worry about memory usage are quite understandable. If you configure MySQL Server so it uses too small amount of memory it will likey perform suboptimally. […]
May 16, 2006 |
Insight for DBAs
I’ve now added one more presentation to MySQL Performance Presentations page. This presentation is from MySQL Users Conference 2006 which was presented by Vadim but which we prepared together. Hope you enjoy it. Get it here
May 13, 2006 |
Insight for DBAs
MyISAM storage engine has key compression which makes its indexes much smaller, allowing better fit in caches and so improving performance dramatically. Actually packed indexes not a bit longer rows is frequent reason of MyISAM performing better than Innodb. In this article I’ll get in a bit more details about packed keys and performance implications […]
May 11, 2006 |
Insight for DBAs
Thinking more about the problems I wrote about yesterday I had a question why so ugly workaround and guesses or manual configuration is needed ? The answer seems to be Operation Interfaces just do not provide IO interface which is good enough. The big missing piece is priority. There are process and threads priorities in […]
May 10, 2006 |
Insight for DBAs
As you might know Innodb storage engines uses Fuzzy Checkpointing technique as part of it recovery strategy. It is very nice approach which means database never needs to “stall” to perform total modified pages flush but instead flushing of dirty pages happens gradually in small chunks so database load is very even. This works great […]