O'Reilly logo

PostgreSQL 9.0 High Performance by Gregory Smith

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Analyzing buffer cache contents

You've seen and been told how using a block will increase its usage count. You've also seen and been told how a dirty block might make its way out to disk. This wasn't intended just as an academic exercise. Believe it or not, all of this information is useful for determining how large your shared buffer cache should be!

If you want to do better than following a rule of thumb for how big to set shared_buffers relative to the OS cache, you have two options. You can run your own benchmarks with your application and see how the results vary, based on the amount of shared memory dedicated to the database. Just be careful to account for the influence of the larger OS cache when running multiple such tests, or you can use ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required