Vacuum and autovacuum
In this recipe, we will be discussing the importance of vacuum and autovacuum in achieving good PostgreSQL performance.
Getting ready
As aforementioned, PostgreSQL is based on MVCC. As a net result, we will have all the non-visible tuples beside visible tuples, which occupy the underlying disk storage. As of now, these non-visible tuples have no use, and if we could reclaim or reuse the non-visible tuple's disk storage, that would make the disk utilization more effective.
How to do it...
Let's experiment with the usage of VACUUM by creating a sample table and executing a few SQL statements that generate non-visible tuples or dead tuples.
Connect to your database using psql as a super user and then execute the following command: ...
Get PostgreSQL High Performance Cookbook now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
