At Percona Live last week, someone showed me a graph from their Cacti monitoring system, using the templates that I wrote. It was the buffer pool pages read, written, and created. He asked me if the graph was okay. Shouldn’t there be a lot more pages read than written, he asked? It’s a great question. [...]
MySQL caching methods and tips
“The least expensive query is the query you never run.” Data access is expensive for your application. It often requires CPU, network and disk access, all of which can take a lot of time. Using less computing resources, particularly in the cloud, results in decreased overall operational costs, so caches provide real value by avoiding [...]
Virident tachIOn: New player on Flash PCI-E cards market
(Note: The review was done as part of our consulting practice, but is totally independent and fully reflects our opinion) In my talk on MySQL Conference and Expo 2010 “An Overview of Flash Storage for Databases” I mentioned that most likely there are other players coming soon. I actually was not aware about any real [...]
On Good Instrumentation
In so many cases troubleshooting applications I keep thinking how much more efficient things could be going if only there would be a good instrumentation available. Most of applications out there have very little code to help understand what is going on and if it is there it is frequently looking at some metrics which [...]
How innodb_open_files affects performance
Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable – innodb_open_files which defines how many files Innodb will keep open while working in innodb_file_per_table mode. Unlike MyISAM Innodb does not have to keep open file descriptor [...]
Tokyo Tyrant – The Extras Part II : The Performance Wall
Continuing my look at Tokyo Tyrant/Cabinet and addressing some of the concerns I have seen people have brought up this is post #2. #2. As your data grows does Tokyo Cabinet slow down? Yes your performance can degrade. One obvious performance decrease with a larger dataset is you start to increase the likelihood that your [...]
MySQL-Memcached or NOSQL Tokyo Tyrant – part 2
Part 1 of our series set-up our “test” application and looked at boosting performance of the application by buffer MySQL with memcached. Our test application is simple and requires only 3 basic operations per transaction 2 reads and 1 write. Using memcached combined with MySQL we ended up nearly getting a 10X performance boost from [...]
Predicting Performance improvements from memory increase
One common question I guess is how much should I see performance improved in case I increase memory say from 16GB to 32GB. The benefit indeed can be very application dependent – if you have working set of say 30GB with uniform data access raising memory from 16GB to 32GB can improve performance order of [...]
How multiple disks can benefit for single client workload ?
Let us talk few more about disks. You might have read my previous post and Matt’s Reply and it looks like there are few more things to clarify and explain. Before I get to main topic of the article lets comment on IO vs Disk question. If you look at Disk Based databases all data [...]
A note about Pythian
On Monday I had a chance to have a chat with Paul Vallee from Pythian. This was quite an enlightening talk, and I was very impressed by Paul openness and willing to share with me a lot of internal operations details. I wish there would be more people out where as open and helpful even [...]

