July 30, 2014

PBXT benchmarks

The PBXT Storage Engine (http://www.primebase.com/xt/) is getting stable and we decided to benchmark it in different workloads. This time I tested only READ queries, similar to ones in benchmark InnoDB vs MyISAM vs Falcon (http://www.mysqlperformanceblog.com/2007/01/08/innodb-vs-myisam-vs-falcon-benchmarks-part-1) The difference is I used new sysbench with Lua scripting language, so all queries were scripted for sysbench.

Interesting MySQL and PostgreSQL Benchmarks

I had found pile of MySQL and PostgreSQL benchmarks on various platforms which I have not seen before. Very interesting reading. It does not share too much information about how MySQL or PostgreSQL was configured or about queries. Furthermore MySQL and PostgreSQL has a bit different implementations (ie SubQueries avoided for MySQL) so do not […]

Internals of InnoDB mutexes

InnoDB uses its own mutexes and read-write locks instead of POSIX-mutexes pthread_mutex*, the main reason for that is performance, but InnoDB’s implementation isn’t ideal and on modern SMP boxes can cause serious performance problems. Let’s look on InnoDB mutex (schematic for simplification):

MyISAM concurrent insert

Arjen posted a good note about MyISAM concurrent-insert features, though I should mention concurrent-insert can be cause of scalablity and peformance problems on SMP boxes, especially on queries processing range-queries. The reason of problems is POSIX read-write locks, which are used to protect key_buffer from concurrent changes and called for each processed row. More info […]