James Pearson wrote: > m.r...@5-cent.us 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 ... > What kind of filesystem is it? I note that xfs also has barrier as a mount option.
mark _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos