Want to get Unix/Linux techies arguing? Besides classic flame wars such as whether vi or EMACS is the better text editor, another surefire way to start a fight is to talk about which file systems are the best. Google, which knows a thing or two about fast systems has decided, for their purposes anyway, that Ext4 is the best and close to the fastest file system of all.
In a recent note to the Ext4 developer mailing list, Google's Michael Rubin, a senior staff engineer, wrote, "Google is currently in the middle of upgrading from ext2 to a more up to date file system. We ended up choosing ext4."