The following features are provided by pgpool:
Connection pooling
Statement-level replication
Load balancing
Limiting connections
In-memory caching
Tip
When deciding which features to use, it is important to keep in mind that not all functionality is available at the same time. The following website contains an overview of what can go together and what cannot:
One core feature of pgpool is the ability to do connection pooling. The idea is pretty much the same as the one we outlined in the previous chapter. We want to reduce the impact of forking connections each and every time a webpage is opened. Instead, we want to keep connections open and reuse them whenever a new request comes along. Those concepts have already been discussed for PgBouncer in the previous chapter.
In addition to pooling, pgpool provides basic replication infrastructure made explicitly to increase a system's reliability. The thing here...