>> Personally, I managed a machine which typically had 3000 users >> running queries against it while about 20 million >> INSERT/UPDATE/DELETE statements per day were run against it. >> Tuning showed best performance when we used connection pools >> with 35 connections for read-only queries and 6 connections for >> the DML.
> May I know the machine configuration esp. the hardware > configuration that you used for this setup?
It had 16 cores and 256GB RAM, a RAID controller with 256MB battery-backed RAM configured for write-back for a 40 drive RAID 5 array, with a separate BBU controller for a RAID 1 pair for the OS and another for the WAL (pg_xlog directory).
Oh, and the database was over 3TB and growing fairly quickly.