I was struck by that too, and came here to make the same comment.

Why do you suppose they went with XFS? Ext4 seems like the defacto file system these days, but I know a lot of people seem to prefer XFS for one reason or another. It's a surprise to me that RHEL decided to default too it.

Anybody care to shed some light?

It's all about expected disk sizes in 10 years time (when RHEL 7 main support ends). Ext4 scales up to around 16 TB -- I know it theoretically can support a much larger volume size, but in practice it doesn't work so well. XFS handles tens of terabytes without a problem and Red Hat has been supporting huge XFS volumes for years with many customers (who in earlier versions of RHEL paid extra for that support).

http://lwn.net/Articles/573690/ Dave is a redhat employee.

Dave Chinner's talk is great: http://www.youtube.com/watch?v=FegjLbCnoBw

Their gluster server offering also uses XFS, so probably for support reasons, they saw XFS had better long term support for both sets of users.

seriously recommend people who care their data on disk to use ext4. http://lwn.net/Articles/476263/ XFS behaves not so well on power failure case.

That is pretty much 12 months old does it still apply?

I remember using XFS some years ago. It was blazing fast for anything involving large files.

It also had a bug, in that a power failure or kernel crash was liable to truncate some freshly-written open files to zero size. Anyone knows if this problem has been eliminated?

Not sure actually, pretty bold of RH but they have put a ton of dev time behind it with gluster so I guess it only makes sense.