May 24, 2013

table_cache negative scalability

Couple of months ago there was a post by FreshBooks on getting great performance improvements by lowering table_cache variable. So I decided to investigate what is really happening here. The “common sense” approach to tuning caches is to get them as large as you can if you have enough resources (such as memory). With MySQL [...]

XtraDB Amazon Image

For those who use Amazon EC2 service and were anxious about having XtraDB ready to launch there is a good news. We created a public AMI (Amazon Machine Image) with XtraDB release 8 installed on CentOS 5.3. How to use it. First make sure it is avaiable.

Run it. It is built for x86_64 [...]

SystemTap – DTrace for Linux ?

Since DTrace was released for Solaris I am missing it on Linux systems… It can’t be included in Linux by the same reason why ZFS can’t be – it’s licensing issue. Both ZFS and DTrace are under CDDL, which is incompatible with GPL. So you can see DTrace and ZFS on Solaris, FreeBSD, MacOS, but [...]