Look at the format of the device class for the drives.
If you let it default to "DRIVE" it will use all available hardware
compression...
I always tell clients to use compression and I also have the drives set to
use compression.
tsm: TSMSRV10>q dev f=d
Device Class Name: 3590E1A
Device Access Strategy: Sequential
Storage Pool Count: 6
Device Type: 3590
Format: DRIVE
<stuff deleted>
Syntax
>>-DEFine DEVclass--device_class_name----DEVType--=--3590------->
.-FORMAT--=--DRIVE-------.
>-----+------------------------+--LIBRary--=--library_name------>
'-FORMAT--=--+-DRIVE---+-'
+-3590B---+
+-3590C---+
+-3590E-B-+
'-3590E-C-'
<stuff deleted>
FORMAT
Specifies the recording format to be used when writing data to
sequential access media. This parameter is optional; the default value
is DRIVE.
The following are possible values for 3590 devices:
DRIVE
Specifies that TSM selects the highest format that can be
supported by the sequential access drive on which a volume is
mounted.
3590B
Specifies that TSM writes data using the basic (uncompressed)
format. This results in a tape capacity of approximately 10GB.
3590C
Specifies that TSM writes data using the compressed format. This
results in a tape capacity of approximately 10GB. However, this
format uses the tape drive's hardware compression feature so the
actual capacity may be greater depending on the effectiveness of
compression.
3590E-B
Specifies that TSM writes data by using the uncompressed format
similar to the 3590B format. This results in a tape capacity of
approximately 10GB.
3590E-C
Specifies that TSM writes data by using the compressed format
similar to the 3590C format. This results in a tape capacity of
approximately 10GB. However, this format uses the tape drive's
hardware compression feature so the actual capacity may be greater
depending on the effectiveness of compression.
-----Original Message-----
From: Farren Minns [mailto:[EMAIL PROTECTED]]
Sent: Monday, November 19, 2001 5:10 AM
To: [EMAIL PROTECTED]
Subject: Help Please with 3590 Hardware Compression
Fellow TSMers
I have a question regarding compression and 3590 drives. I must apologise
that I am not the most technically minded person, so responses in laymen's
terms are most appreciated.
Set-up
TSM 3.7.3.8 Server running on a Solaris 7 box
Attached to an IBM 3494 library with two 3590 drives
I understand that compression can be done from the client side, but have
been told that hardware compression can be a lot better and quicker. Can
anyone tell me how to find out if 3590 hardware compression is in use, and
how to set it up is it isn't (or pointers in the right direction).
At the moment our drives are enabled as follows:-
Library Name Drive Name Device Type Device ON LINE
------------ ------------ ----------- ----------------
-------------------
3494A DRIVE1 3590 /dev/rmt/3stc Yes
3494A DRIVE2 3590 /dev/rmt/5stc Yes
Thanks in advance for any help
Farren Minns
