On Wed, May 31, 2006 at 03:28:12PM +0200, Roch Bourbonnais - Performance Engineering wrote:
> Hi Grant, this may provide some guidance for your setup; > > it's somewhat theoretical (take it for what it's worth) but > it spells out some of the tradeoffs in the RAID-Z vs Mirror > battle: > > > http://blogs.sun.com/roller/page/roch?entry=when_to_and_not_to thanks, that is very useful information. it pretty much rules out raid-z for this workload with any reasonable configuration I can dream up with only 12 disks available. it looks like mirroring is going to provide higher write IOPS and increased redundancy, obviously at the expense of the available space. > As for serving NFS, the user experience is very much > impacted by the I/O latency, so any form of 'persistent' RAM > on the server side allows NFS to service frequent commit > operations without having to wait for rotational latency. indeed, that is what I'm hoping for. delivery to maildir format mailboxes is rather commit intensive, so anything that can reduce latency and squeeze extra IOPS out of the storage is a big win. I'm sure there will be some NFS parameters to tweak, but that's a separate issue :) grant. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
