High Performance PostgreSQL for Rails

Basics of Autovacuum

Automatic Vacuum, or Autovacuum,^[224] is a background scheduler that runs VACUUM workers for each table. The scheduler process runs by default when PostgreSQL starts.

Autovacuum thresholds are configurable and are considered conservative by default. Thresholds can be tuned using various parameters. When facing problems where Autovacuum can help, administrators often add more resources so that it runs more frequently.

Autovacuum is conservative by default so that it runs on lower-powered servers and doesn’t disrupt other operations. Adding more resources to Autovacuum can be surprising, but it makes sense when considering that heavily loaded systems should get a proportional increase in resource allocation to keep up.

If ...