I am frequently asked by potential customers with high I/O requirements if they can use Linux instead of AIX or Solaris.

Can Linux file systems, which I will define as ext-4, XFS and xxx, match the performance of file systems on other UNIX-based large SMP servers such as IBM and Sun? Some might also inquire about SGI, but SGI has something called ProPack, which has a number of optimizations to Linux for high-speed I/O, and SGI also has their open proprietary Linux file system called CxFS, which is not part of standard Linux distributions. Because SGI ProPack and CxFS are not part of standard Linux distributions, we won't consider them here. We'll stick to standard Linux because that is what most people use.

We'll focus on two areas:

1. Linux as an operating system, and
2. Linux file systems.

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