From Windows to Linux: Filesystem Culture

  • There are many cultural surprises as one moves from the Windows world to the Linux world. One that most people would not guess is the difference in filesystem culture. This same difference tends to exist coming from other UNIX systems to Linux as well.

    Outside of the Linux world, it is pretty typical for an operating system to have a single, primary use filesystem or possibly two. Traditionally this was UFS on Solaris and BSD, JFS on AIX, XFS on Irix, VxMS on HP-UX, Mac OSX with HFS+ and NTFS on Windows. In recent years, as all of these systems age, some new filesystems have entered the market and nearly all have a more traditional filesystem and a modern one used for specific purposes. Solaris and FreeBSD have added ZFS, Dragonfly has added Hammer and Windows has added ReFS.

    The major exception to this is Linux which has no singular default file system, often uses multiple filesystems and is constantly changing filesystem preferences. Linux users are often overwhelmed with filesystem selection options. Linux has its own filesystems, more than any other OS, and also adopts nearly all filesystem options from everyone else, as well. Linux admins tends to be very aware of their filessytems, know their limitations and mix and match to get the right mix of features, scalability, performance and reliability. Linux also has two different layers of logical volume management, as does Solaris, but is generally an uncommon feature. Linux has multiple approaches available to software RAID, too. Linux is just full of choices, it's part of the culture.

    New admins to Linux are often shocked to find that something that is simply "a part of the OS" everywhere else is a rather big decision point on Linux systems. Of course, for normal cases, whatever OS you are using has a default and it will work just fine. New Linux users tend to panic when presented with choices and forget that they are only choices and that simple defaults are presented. The need to add complexity is purely at the option of the Linux admin.

    But any discussion in Linux circles and you are likely to hear about filesystems in a way that no other administration group even considers. Storage in Linux is truly a different world. It is, however, one of the reasons that Linux Admins are so highly sought after, they tend to have more knowledge and experience and can provide more value in an area such as this where Linux provides more opportunities for careful tuning.