The reason that you see 100G is simple, when the client did already the
compression, the compression on the drive is around 0%, so that's why you
see no compression on tape.
There is not a lot of difference between compression by client or by drive.
So, if you have enough networkbandwidth, it's better to compress by drive,
that's faster, becaurse you need less proccesorcycles on the client;
drivecompression is for "free". And we dutch like that ;-)
Maurice van 't Loo
The Netherlands
----- Original Message -----
From: "Joshua S. Bassi" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, August 28, 2001 7:05 AM
Subject: Re: Question about compression
> The quick answer is to turn off client software compression. But this
> depends on other factors which you can find in the list archives at
> www.adsm.org.
>
>
> --
> Joshua S. Bassi
> Independent IT Consultant
> IBM Certified - AIX/HACMP, SAN, Shark
> Tivoli Certified Consultant- ADSM/TSM
> Cell (408)&(831) 332-4006
> [EMAIL PROTECTED]
>
> -----Original Message-----
> From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED]] On Behalf Of
> Jeff Keen
> Sent: Tuesday, August 28, 2001 9:01 AM
> To: [EMAIL PROTECTED]
> Subject: Question about compression
>
> We have 2 3580 drives with the 3583 changer. The devclass for these
> drives shows them being of format=ultriumc, which I assume means
> compressed. I have compression turned on at the clients. Are my drives
> also compressing, or is there more to setting up drive compression than
> formatting with the ultriumc option? When my tapes are first checked in
> they show estimated capacity of about 200GB, once they are used and
> "full" they show an estimated capacity of about 100GB.
>
> Also, is there a "best" way to compress, or does it differ depending on
> disk space, processor, backup window, etc.
>
> Thanks in advance,
>
> Jeff
>
