Is PostgreSQL suited to one OS? Is it better on Linux than Windows?

I have been running PostgreSQL on Windows Server 2003 without a hitch and its fast, so to answer my own question it seems fine.

However I am about to launch a new project and am considering using a Linux box instead as stability and performance are crucial. Since PostgreSQL seems to be developed on Linux distributions mostly, maybe it would be better to stick with Linux?

PostgreSQL will definitely run faster on Linux than on Windows (and I say this as one of the guys who wrote the windows port of it..) It is designed for a Unix style architecture, and implements this same architecture on Windows, which means it does a number of things that Windows isn't designed to do well. It works fine, but it doesn't perform as well.

For example, PostgreSQL uses a process-per-connection model, not threading. Windows is designed to do threading. If your application does lots of connect and disconnects, it will definitely run significantly slower on Windows, for example.

There is also some assumptions around the filesystem which don't exactly favor NTFS.

The one thing you really need to think about - if you are on Windows, most antivirus products will bug out when used with PostgreSQL, because they are not used to this type of workload (such as 1000 different processes reading and writing to the same file through different handles). That means that the strong recommendation is to always uninstall any antivirus if possible (just disabling it or excluding the PostgreSQL processes/files is often not enough). And this is not just for performance reasons, but also stability under load.

This is hard to answer: As Ken noted, Postgres doesn't make any differences between the OS and it is as stable/unstable in Windows as it is on Linux.

The only real answer to this question is: try it.

Set up a Linux server and a Windows server with the same specs, use the same amount of data on both machines and run your tests.

PS: This has close votes because it may be better asked at serverfault

It is my understanding that, for the same hardware, you will get better performance on Linux as opposed to Windows. Also, while Postgres does run on windows, it has been running on *nix for much, much longer. YMMV of course depending on your situation.

A really good reference on Postgres performance is "PostgreSQL 9.0 High Performance" (https://www.packtpub.com/postgresql-9-0-high-performance/book). The title is a bit of a misnomer as it covers more than just version 9.0.