“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 [...]
Percona Server now both SQL and NOSQL
Just yesterday we released Percona Server 5.1.52-12.3 which includes HandlerSocket. This is third-party plugin, developed by Akira Higuci, DeNA Co., Ltd and explained in Yoshinori Matsunobu’s blog post. What is so special about it: It provides NOSQL-like requests to data stored in XtraDB. So in the same time you can access your data in SQL [...]
Cache Miss Storm
I worked on the problem recently which showed itself as rather low MySQL load (probably 5% CPU usage and close to zero IO) would spike to have hundreds instances of threads running at the same time, causing intense utilization spike and server very unresponsive for anywhere from half a minute to ten minutes until everything [...]
Introducing tcprstat, a TCP response time tool
Ignacio Nin and I (mostly Ignacio) have worked together to create tcprstat[1], a new tool that times TCP requests and prints out statistics on them. The output looks somewhat like vmstat or iostat, but we’ve chosen the statistics carefully so you can compute meaningful things about your TCP traffic. What is this good for? In [...]
Caching could be the last thing you want to do
I recently had a run-in with a very popular PHP ecommerce package which makes me want to voice a recurring mistake I see in how many web applications are architected. What is that mistake? The ecommerce package I was working with depended on caching. Out of the box it couldn’t serve 10 pages/second unless I [...]
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 [...]
Beyond great cache hit ratio
I worked with application recently which has great memcached hit ratio – over 99% but yet still has average page response time over 500ms. Reason ? There are hundreds memcached gets and even though they have some 0.4ms response time they add up to add hundreds of ms to the total response time.
Percona sessions at the MySQL conference
Many Percona employees will be at the 2010 MySQL conference. We’ll be giving a lot of informative technical talks on various topics. Here’s a list: Morgan Tocker, Baron Schwartz: Diagnosing and Fixing MySQL Performance Problems Peter Zaitsev: Scaling Applications with Caching, Sharding and Replication Baron Schwartz: EXPLAIN Demystified Vadim Tkachenko: An Overview of Flash Storage [...]
Percona is hiring a consultant
We’re hiring. We are looking for the following qualifications: Expert knowledge of MySQL. Not just “certified” — years of production experience with it. You need to know server internals, for example. You need to be able to do anything from optimizing difficult queries to moving high-volume services between data centers without interruption. Expert knowledge of [...]
Tokyo Tyrant -The Extras Part III : Write Bottleneck
This is part 3 of my Tyrant extra’s, part 1 focused on durability, part 2 focused on the perceived performance wall. #3. Tokyo Cabinet Can have only a single writer thread, bottlenecking performance When writing an application using Tokyo Cabinet only one connection can be opened as a “writerâ€Â while the rest are readers. Tyrant [...]

