>-----Original Message----- >From: pgsql-performance-owner@postgresql.org [mailto:pgsql-performance- > >> Hi everyone, >> What is the best Linux flavor for server which runs postgres alone. >> The postgres must handle greater number of database around 200+. >Performance >> on speed is the vital factor. >> Is it FreeBSD, CentOS, Fedora, Redhat xxx?? > >As others mention FreeBSD is somewhat different from the others. I >personally prefer FreeBSD because that it what I do best. If you don't >have any prior experiences with FreeBSD/Linux spent some time >installing them and install some ports/apps. Try to become aquainted >with the update tools using the command line interface, csup on >FreeBSD, apt on debian/ubuntu.
I'm running Postgres on NetBSD and RHEL4. I haven't noticed any particular differences in Postgres performance due to the OS, but then again I haven't performed any kind of formal benchmarks, nor am I really stressing the database all that much (most of the time). My preference for OS to run is NetBSD, because I'm most familiar with it and there have been some fairly significant recent focus on performance improvements. If you're really worried about getting the best performance I think you're just going to have to try a few different OSes and see if you notice a difference.
btw, do you mean 200+ databases in a single postgres server, or that many different postgres servers? Running 200 different servers sounds like it might be problematic on any OS due to the amount of shared memory that'll need to be allocated.