From: Ski K. <kac...@gm...> - 2009-04-09 15:18:05
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On Thu, 2009-04-09 at 07:45 -0500, Les Mikesell wrote: > Thomas Karcher wrote: > > Hi Ski, > > > >>> Performance is of course not really great but surprisingly good. I > >>> evaluated (very shortly) against mounting via NFS, and NFS just sucks > >>> with backuppc. > >> I think it depends on the NFS server you are using. I have over 1500 > >> clients backing up via 7 backuppc servers attached via nfs to a high > >> performance Exastore NAS device. Works great. > > > > Ah, yes, that's possible, I have a much "cheaper" environment - and also > > a setup smaller by magnitudes. I had the impression that many very small > > disk accesses (as backuppc does when checking for newer file version > > etc.) is already a bad disk usage pattern by itself. And NFS didn't > > handle it better either ... > > > > Anyway, nice to know that a specialized NAS device could help there. > > Usually you are waiting on disk head motion - and if you run nfs in sync > mode you wait for completion on every write. The things that can help > are lots of physical disks in the volume (better odds for the head to > already be near the right place) and running async with lots of > buffering. Expensive devices might even have some battery-backed or > nonvolatile buffering. > yep, the NAS head has a lot, lot of buffering that is battery backed so the writes complete pretty quickly. ski -- "When we try to pick out anything by itself, we find it connected to the entire universe" John Muir Chris "Ski" Kacoroski, kac...@gm..., 206-501-9803 or ski98033 on most IM services |