HP Microserver ZFS benchmark with dedup

zfs-linux

I have a HP MicroServer which I’m very satisfied with. I bought this right away when HP announced it when it still didn’t have a retail price determined. The only downside of it that it has only soft-RAID (or fake-RAID) controller built-in. A proper HP Smart Array controller must have … Continue reading

BitTornado library forked by me on GitHub

I just forked and committed some patches to the BitTornado library on GitHub.

https://github.com/charlesnagy/BitTornado

Right now I only committed basic fixes to be able to use it in our environment (Python 2.7). Namely:

MySQL 5.6 mysql_install_db script problem

We’re always testing the latest versions of MySQL with most of the environments to make sure that we can find the critical issues before it goes to production. This wasn’t different with the 5.6 MySQL neither. We already started to play with this version in the summer. The first news … Continue reading

MySQL Benchmark – updates by primary vs secondary keys

wrong_tool_for_the_job_by_raresdk-d35viqj

(Note: when I’m talking about MySQL I usually assume InnoDB storage engine. Any other case I explicitly tell this is MyISAM or Memory etc.)

I’ve heared an interesting aproach of using Master-slave replication in MySQL.

Thesis

So the theory was that since updates by primary keys are fast and by … Continue reading

Sleeping connections

Why is it so important to close connections to databases if there’s no explicit need to keep them open (which usually the case)?

Symptoms

  • Icinga reports high usage of allowed connections (>90%) on master MySQL server.
  • No running queries or any specific in processlist. All the connections are sleeping … Continue reading