Re: What's size of your PostgreSQL Database?

>> 7. How many concurrent readers of your database, and what's the average transfer rate, suppose all readers are doing one table scaning.
>
> Concurrent but idle connections in production are around 600. Active
> connections at a time are in the dozens. I can read at about 60 to 70
> Megs a second for random access and around 350 to 400 Megs a second
> for sequential reads.
>

I am not so familiar with PostgreSQL, it uses a one process per connection architecture, let me say one agent process per client , what I am wondering is how multiple agent process share page caches. In many other databases, client agents uses the multiple thread method, so they can share memory buffers within the same process, are there share-memory mechanisms between PostgreSQL agent processes?