m.roth@xxxxxxxxx wrote:
Matt Garman wrote:
We have a "compute cluster" of about 100 machines that do a read-only
NFS mount to a big NAS filer (a NetApp FAS6280). The jobs running on
these boxes are analysis/simulation jobs that constantly read data off
the NAS.
<snip>
*IF* I understand you, I've got one question: what parms are you using to
mount the storage? We had *real* performance problems when we went from 5
to 6 - as in, unzipping a 26M file to 107M, while writing to an
NFS-mounted drive, went from 30 sec or so to a *timed* 7 min. The final
answer was that once we mounted the NFS filesystem with nobarrier in fstab
instead of default, the time dropped to 35 or 40 sec again.
barrier is in 6, and tries to make writes atomic transactions; its intent
is to protect in case of things like power failure. Esp. if you're on
UPSes, nobarrier is the way to go.
The server in this case isn't a Linux box with an ext4 file system - so
that won't help ...
James Pearson
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
http://lists.centos.org/mailman/listinfo/centos
