Re: Question about compression

2001-08-29 Thread Maurice van 't Loo

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




Question about compression

2001-08-28 Thread Jeff Keen

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



Re: Question about compression

2001-08-28 Thread Joshua S. Bassi

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