February 11, 2012

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 [...]

Queries Active vs Transactions Active

What is wrong here (the part of SHOW INNODB STATUS): ————– ROW OPERATIONS ————– 8 queries inside InnoDB, 9 queries in queue 100 read views open inside InnoDB It is relationship between queries active – queries inside innodb+queries in the queue totalling 17 with “read views open inside InnoDB” which is a fancy way of [...]

Statistics of InnoDB tables and indexes available in xtrabackup

If you ever wondered how big is that or another index in InnoDB … you had to calculate it yourself by multiplying size of row (which I should add is harder in the case of a VARCHAR – since you need to estimate average length) on count of records. And it still would be quite [...]