That's interesting, are you multiplexing with multiple servers? Cause from
limited testing, I've found that doing more than one vos dump at once to the
same server doesn't actually increase your data rate any, or increases it
only a tiny amount. If the disks on the server were the bottleneck, it would
have a more noticable effect I'm sure.
-- Nathan
> -----Original Message-----
> From: David Thompson [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, October 03, 2000 9:12 AM
> To: Neulinger, Nathan R.
> Cc: 'Brian T. Huntley'; Paul Blackburn; [EMAIL PROTECTED]
> Subject: Re: AFS backup/restore using ADSM
>
>
> "Neulinger, Nathan R." wrote:
> >It might be worth considering the AfsWebSecure approach -
> which bypasses the
> >cache entirely. Although you'd have to come up with client
> code at that
> >point to integrate directly into the tool you were using.
> >
> >The biggest problem we've run into with backups is that the
> volume dumps are
> >just so slow. On a server that we can pull 25 MB/sec
> sustained off the
> >disks, we still can't get any more than 3MB/sec or so with vos dump.
> >
> >I believe my next backup approach is going to be putting a
> server in between
> >the backup host and the file servers, and somehow
> interleaving (or starting
> >in parallel in some fashion) multiple vos dump processes.
> One to each file
> >server. It'll mean a bunch of extra space would be required
> on that machine,
> >but hey, 40GB IDE disks are cheap.
>
> From the 'easier said than done' department: It sounds to me like the
> answer is to get rid of the performance problems in the volserver :)
>
> We use vos dump, with a backup system that allows us to multiplex
> multiple backup streams onto a single tape. We run as many as 6
> simultaneous vos dumps against an afs server to keep the data rates
> up.
>
> We have also considered using 'staging' disks on our backup servers;
> we've been able to avoid it up to this point.
>
> --
> Dave Thompson <[EMAIL PROTECTED]>
>
> Associate Researcher Department of Computer Science
> University of Wisconsin-Madison http://www.cs.wisc.edu/~thomas
> 1210 West Dayton Street Phone: (608)-262-1017
> Madison, WI 53706-1685 Fax: (608)-262-6626
> --
>
>
>
