On Tue, Oct 7, 2014 at 2:40 PM, Roger Luedecke <roger.luedecke@gmail.com> wrote:
I know that SLED is using XFS for it's home and that is part of why we are using it. Why this choice? Why not EXT4 as in the past or btrfs like root? I've heard reasons why it's better but could someone elaborate on the underlying mechanisms leading to the superiority of XFS for the home partition?
-- I think I have this right. Listen to that video link to confirm, or just post to the XFS mailing list and ask Dave Chinner to review the below text: ============= XFS was designed for high-end systems including supercomputers. The design is 20 years old, so many of the features it incorporates work well on current multi-core laptops and PCs. During the decade from 2000-2010, XFS had a well deserved reputation of working very inefficiently with small files. In the 2010/2011 timeframe XFS received major improvements related to metadata handling. This had a huge positive impact on how well XFS works with small files. The key concept is that journal is now maintained initially in RAM. Prior to streaming a large junk of journal information to the disk journal, it is now elevator sorted. That means when the actual on disk updates are done by applying the journal, the disk head will follow a series of disk seeks all in the same direction. This drastically cut down on long disk head seeks when working applying the journal. The end result was drastically faster speeds when working with small files on rotating media. ext4 on the other hand was designed for previoius generation computers. Although it can scale to the sizes needed today, it simply was not designed to handle that heavy workloads and massive scaling that modern laptops and desktops can demand. As such, ext4 is rapidly approaching end of life. The envisioned replacement for ext4 for the last several years has been btrfs. Unfortunately, btrfs has not yet achieved the performance levels needed to take on heavy workloads. ============ All of the above is from my memory of the video. I watched it a year or more ago, so those with more current knowledge please correct as appropriate. Greg -- Greg Freemyer -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org