ADSM-L

Re: TSM DB/Disk Pool - Disk tuning question

2001-08-30 15:57:37
Subject: Re: TSM DB/Disk Pool - Disk tuning question
From: Lindsay Morris <lmorris AT SERVERGRAPH DOT COM>
Date: Thu, 30 Aug 2001 15:56:48 -0400
Jeff, clever! run iostat, then watch sessions start and land on different
physical disks, on by one.
Like the idea.

But what happens when you run out of volumes? Say you have 8 disk volumes,
and 9 sessions.
Does the ninth session just hang, until one of the first 8 finishes?
Or does the ninth session grab some busy volume, sharing it with another
session?

> -----Original Message-----
> From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]On Behalf Of
> Jeff Bach
> Sent: Thursday, August 30, 2001 3:49 PM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: Re: TSM DB/Disk Pool - Disk tuning question
>
>
> 1.  A single backups runs to a single volume as perceived by ADSM.  The
> first session runs to the first volume allocated to the storage pool.  The
> second session runs to the second logical volume allocated to the storage
> pool.  The third sessions to the third volume.
>
> With THIS understanding, you can effectively stripe by allocating volume 1
> from each drive first, then allocate the second volume from each
> drive.  You
> can see the threads using "show threads".  Run one session, watch iostat,
> then start a second and third.  You should be able to see what my
> understanding it easy enough (or at least tell me I am wrong)