[OpenAFS] Re: why afs backup is so poorly supported

chas williams - CONTRACTOR chas@cmf.nrl.navy.mil
Thu, 12 Oct 2006 10:55:28 -0400

In message <49EFC09F-F22F-4935-A487-B99CD855137F@umich.edu>,Steve Simmons write
>Inversions file system, a project which built a fs on top of  
>University Ingres. It was presented at a USENIX.  As I recall, they  
>claimed somewhere about a 2:1 overhead in general.

it depends on how this was measured.  user -> kernel -> native fs
is going to go pretty well since you dont have the extra copy
back to userspace.  user -> kernel -> userspace db is not going to
perform well due to the extra copy.  the afs fileserver wouldnt
see this same penalty.