Re: formatsize and volumes in diskpool

        I don't believe anyone has poked at this so I will.

        If it were something like RAID5, RAID10 RAID0+1, then you can
create more volumes per LUN. Heck you can stripe, mirror or even
"plaid". There has been lots of discussions on here about the many ways
to go about that. 

        If you are using JBOD, I believe the recommendation is to still
create 1 volume for each disk to avoid head contention. Some people
argue that you could get away with 2 per disk.
        
        So in your case, I would suppose you would create 2 50GB
volumes. Mirroring is always nice on a storagepool, but you would need
to do that at the OS or hardware, as you cannot do it within the TSM
server. 

Ben


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
J. Sum
Sent: Thursday, April 13, 2006 5:41 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: formatsize and volumes in diskpool

This is a qustion of what is the best or right way to adding volumes to
a diskpool, specifically about "formatsize" option.

I have a primary diskpool which has 2X5GB volumes on 2 harddrives. Now I
have about 100GB free space ( 2 X 50Gb harddrive ) I want to add to the
diskpool.

My question is:

a. Do I need to keep the formatsize the same as the existing volumes?
Say, specify 20 X 5GB volumes and add to the pool?

b. If say no to question a. Do I better to create 10 X 10GB volumes or 2
X 50Gb volumes? does that affect performance if the the volumes are on
different HDs?

c. Just with to confirm the command to do so is:

def vol <stgpool-name> <file-in-partision> formatsize=<mb>


Thanks in advance for your advice

JinGsuM.