Amanda-Users

Re: hardware vs software compression (was Re: amflush/amcheck not in sync?)

2003-04-25 10:38:28
Subject: Re: hardware vs software compression (was Re: amflush/amcheck not in sync?)
From: Russell Adams <RLAdams AT kelsey-seybold DOT com>
To: amanda-users AT amanda DOT org
Date: Fri, 25 Apr 2003 09:34:00 -0500
Arg!

We put in the extra buses (KZPBA), one per TL892 library, to give them plenty
of bandwidth... Obviously they are underutilized.

Is that 8MB/s per drive? I wish! ;]

Russell

On Fri, Apr 25, 2003 at 10:05:41AM -0400, Steve Thompson wrote:
> On Thu, 24 Apr 2003, Russell Adams wrote:
> 
> > The host runs OpenVMS, and the only reason this is relevant is because
> > I'm constantly wishing I could run AMANDA on this platform. VMS's
> > BACKUP utility doesn't support compression, or anything else for that
> > matter. Our backups are done by custom scripts. If I ran Tru64 or
> > Linux on these, I'd be using AMANDA.
> > [...] 
> > In uncompressed mode I get 4-5MB/s, in compressed its 800KB/s. Sad
> > really.
> 
> Definitely something wrong here. I am using VMS BACKUP to write to some
> TZ89 drives from an ES40 using hardware compression. I get on average
> about 8 MB/sec. The system has six TZ89 drives on two buses and can write
> at that speed to all six simultaneously.
> 
> Steve
> ------------------------------------------------------------------------------
> Steve Thompson                 E-mail:     smt AT corning DOT com
> @ Corning, Incorporated        Office:     (607) 974 2659
> Sullivan Park Data Center      FAX:        (607) 974 3964
> Painted Post, NY 14870         Cell:       (607) 725 1167
>   "186,300 miles per second: it's not just a good idea, it's the law"
> ------------------------------------------------------------------------------