ADSM-L

Re: LTO throughput - real world experiences

2003-07-08 16:28:45
Subject: Re: LTO throughput - real world experiences
From: Chris Murphy <cmurphy AT IDL.STATE.ID DOT US>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Tue, 8 Jul 2003 14:29:34 -0600
>What is the best way to determine what your throughput is for each process?
Are you just going by the activity log?

I have measured it a couple of ways.  As many have said, from the switch
ports is an excellent (though manual) process.  Be warned there is a slight
FC overhead on every frame, and as I recall, the numbers on most switches is
the gross throughput (includes overhead), not net.

I have also used the TDP data for Exchange, which logs the throughput speed
from TSMs' perspective.  This is where we achieve around 15MB/s which I
think is about all our little Exchange box can push to be honest.

Thirdly, depending on your disk arrays, some have utils that will give info
as well.  We use a FAStT box and which has LUN's specifically assigned to
storage pools.  I can get some idea of its ability through the management
util (IBM FAStT Storage Manager) for it, but also have to weary of other
activity on that array, of course.


Chris