ADSM-L

Re: [ADSM-L] the purpose of "file" device class

2009-09-21 06:27:47
Subject: Re: [ADSM-L] the purpose of "file" device class
From: km <km AT GROGG DOT ORG>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Mon, 21 Sep 2009 12:23:32 +0200
On 21/09, Mehdi Salehi wrote:
> Hi,
> What is actually the different between a disk pool and a file pool? Both are
> based on disks and the latter behaves sequentially like tapes. What makes
> necessary to have these two types of pools in TSM? Couldn't IBM eliminate
> one of them and say that there is only one disk-based pool?
>
> Thanks

DISK storage pools are prone to fragmentation which FILE stgpools are
not (if you pre-allocate volumes).

DISK storagepools are therefore used as intermediary storage whereas FILE
stgpools are more of a replacement for tape to mitigate tape mount times
and number of mount points, think VTL.

I would hazard a guess that architectural differences are described more
in detail in a redbook, maybe the TSM concepts guide or the TSM technical
guide.

-km