[Edubuntu] For shared (project team) folder, ACLs change group of moved-in files?

[Alkis Georgopoulos]

Στις 24/01/2013 03:00 πμ, ο/η John Hupp έγραψε:
> So with the experience in the Greek schools, can more be said about
> performance?

You don't need other people's advice on something you can easily measure 
yourself.
Here's a comparison between NORMAL, BINDFS, SSHFS and NFS for copying an 
.iso:

================================================================
root at pc:/NORMAL/dir# echo 3 > /proc/sys/vm/drop_caches
root at pc:/NORMAL/dir# time cp ubuntu-12.04.1-desktop-i386.iso \
                              ubuntu-12.04.1-desktop-i386.iso.bak
real	0m29.371s
user	0m0.020s
sys	0m2.048s
CPU (via top): 50% idle, 40% wait
----------------------------------------------------------------
root at pc:/BINDFS/dir# echo 3 > /proc/sys/vm/drop_caches
root at pc:/BINDFS/dir# time cp ubuntu-12.04.1-desktop-i386.iso \
                              ubuntu-12.04.1-desktop-i386.iso.bak
real	0m30.852s
user	0m0.020s
sys	0m2.320s
CPU (via top): 40% idle, 45% wait
----------------------------------------------------------------
root at pc:/SSHFS/dir# echo 3 > /proc/sys/vm/drop_caches
root at pc:/SSHFS/dir# time cp ubuntu-12.04.1-desktop-i386.iso \
                             ubuntu-12.04.1-desktop-i386.iso.bak
real	0m50.056s
user	0m0.020s
sys	0m1.620s
CPU (via top): 5% idle, 15% wait
----------------------------------------------------------------
root at pc:/NFS/dir# echo 3 > /proc/sys/vm/drop_caches
root at pc:/NFS/dir# time cp ubuntu-12.04.1-desktop-i386.iso \
                           ubuntu-12.04.1-desktop-i386.iso.bak
real	0m34.249s
user	0m0.000s
sys	0m1.532s
CPU (via top): 5% idle, 80% wait
================================================================

So that's a 5% drop in performance with bindfs, negligible.
NFS is pretty light too.
On the other hand SSHFS (fat clients, localapps...) takes a heavy toll 
on the server CPU and that reflects on the time needed to perform file 
operations as well.