MySQL Benchmark – updates by primary vs secondary keys

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(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