Re: New 520+ Shipment

Running 8 arms on the embedded controller plus the 5727 doesn't come highly
recommended from our BP or the graphs we've modeled.  The models we ran in
Performance Navigator when planning the system gave us slightly better disk
arm usage graphs when putting 4 arms on the embedded and 4 on the 5776.  We
need the 8 arms moreso for disk arm performance rather than the capacity,
so losing the additional overhead to RAID isn't hurting us. This box is a
Domino/Websphere workload that doesn't impact the CPW immensely, but we've
had disk arm and IOP concerns on the current 800 before we went from 6 arms
on a 5702 (no cache) to a 2757 (SUPER cache).

The Cadillac approach would be to get the expansion and the 5580 setup, but
this would still require half of the 8 drives to be RAIDed on the embedded
controller with the 5580 only driving 4 drives.  There's about a $25K price
differential (with 3 years of HW maint included) in going with that setup,
and we're not sure it's worth it (a decision we're finalizing tomorrow).
The graphs with the CEC only approach seem to show that it should handle
the disk arm/IOP workloads with the embedded/5727/5776 setup.

Also supporting that notion is the fact that we take the current 800's
workload and run it for a day each month on another 520 that has a 5709
controller driving 8 drives (with no apparent performance issues).

Good points about the strategy you mention for larger and partitioned
systems... i'll keep it in mind for future situations we may run in to!
Another situation of ours is that we lease the iSeries/i5 equipment for 3
years typically and when we upgrade or purchase a new one, the complete old
system gets shipped back.


                                                                       
             "Trevor Perry"                                            
             <tperry@cleartech                                         
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             07/06/2006 11:59                                      Subject
             AM                        Re: New 520+ Shipment           
                                                                       
                                                                       
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Chad,

Why are you putting in two disk controllers? Are there two partitions?

There are some reasons why encouraging you to put your disks outside the
CEC
are a good idea. We are finding more and more that if we partition, and put

the drives in expansion units, it is much easier to upgrade. The new CEC
replaces the old CEC and the partitions are already finished - no
unload/reload. The less stuff in the CEC, the better.

Of course, since that applies to larger machines, it does not help the
smaller business. I am sure IBM is listening, and they are incorporating
high speed disk IOP into their iSis design..

Trevor
----- Original Message -----
From: <ChadB@xxxxxxxxxxxxxxxxxxxx>
Subject: Re: New 520+ Shipment



It will be a 1 CPU 7143 520+ with 4GB Ram, 8 35gb drives, 1200/60 CPW.
Pretty far down the food chain... ;)

It will come in around either $60k or $80k after the added MES items
depending on the disk controller approach we choose (5727 and 5776 in CEC
or 5727 in CEC and 5580 in an 0595 expansion).

The discount isn't spec'd yet, but should be in the 15%-18% range i'm
guessing.

As far as features, the worst part is having to add an expansion to run the
2757/2780/5580 type controllers... this is a killer to the small simple
system concept.  The 800 we're upgrading from has the 2757 in the CEC and
is fine.  The current restrictions preventing the souped up controllers in
the CEC is a very bad design IMO.

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