InnoDB scalability issues due to tables without primary keys

Each day there is probably work done to improve performance of the InnoDB storage engine and remove bottlenecks and scalability issues. Hence there was another one I wanted to highlight: Scalability issues due to tables without primary keys. This scalability issue is caused by the usage of tables without primary keys. This issue typically shows itself as contention on the InnoDB dict_sys mutex. Now the dict_sys mutex controls access to the data dictionary. This mutex is used at various important places throughout the InnoDB code and as such any contention on the dict_sys mutex is going to have a InnoDB system-wide negative affect. You can read the rest of the post here.

Ovais is a storage architect with keen focus on reliability, efficiency and performance of OLTP databases, more specifically MySQL. He currently works at Uber on ensuring storage reliability and scalability. Previously, he helped different web properties scale their MySQL infrastructure. He also worked at Percona as a Senior MySQL consultant and at a few other startups in various capacities.

  • Very useful and supportive article. I wish I can do all of that in a short period of time.