So, on a large IBM POWER8 system I was recently running the newly coined “yesmark” benchmark, which is best translated as this:

Benchmark (N for concurrency): for i in {1..N}; do yes "DO 0;" | mysql > /dev/null & done
Live results: mysqladmin -ri 1 extended-status | grep Questions

Which sounds all fun until you realize that it’s *amazingly* close in results to a sysbench point select benchmark these days (well, with MySQL 5.7.7).

Since yesmark doesn’t use InnoDB though, MariaDB is back in the game.

I don’t think it matters between MariaDB and MySQL at this point for yesbench. With MySQL in a KVM guest on a shared 2 socket POWER8 I could get 754kQPS and on a larger system, I could get 1.3 million / sec.

1.3 Million queries / sec is probably the highest number anybody has ever seen out of MySQL or MariaDB, so that’s fairly impressive in itself.

What’s also impressive is that on this workload, mysqld was still only using 50% of CPU in the system. The mysql command line client was really heavy user.

Other users are: 8% completely idle, another 12% in linux scheduler (alarmingly high really). So out of all execution time, only about 44% spent in mysqld, 29% in mysql client.

It seems that the current issues scaling to two socked POWER8 machines are the same as with scaling to other large systems, when we go beyond about 20 POWER8 cores (SMT8), we start to find new and interesting challenges.