Re: VIOS and Perf Monitoring

Rob,

You want to have a standard workload you can test with. At V7 use the wait accounting tooling built in to the OS. A very good test is loading PTFs from an image catalog. On smaller systems ( 4 or < drives) it is often faster to load the CDs one by one than use the image catalog. All I/O. I think it starts to even out at about 6 drives.

Jim Oberholtzer
Chief Technical Architect
Agile Technology Architects


On 8/25/2011 6:57 AM, rob@xxxxxxxxx wrote:

If I was to play around and unload/reload a lpar to test this, what would
be effective measuring?


Rob Berendt
-- Group Dekko Dept 1600 Mail to: 2505 Dekko Drive Garrett, IN 46738 Ship to: Dock 108 6928N 400E Kendallville, IN 46755 http://www.dekko.com From: Kirk Goins <kirkgoins@xxxxxxxxx> To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx> Date: 08/24/2011 05:04 PM Subject: Re: VIOS and Perf Monitoring Sent by: midrange-l-bounces@xxxxxxxxxxxx According to multiple IBM and NON-IBM sources the answer is along these lines... The OS has no idea if these disks are real or virtual. The OS will only queue so many I/Os per disk arm available ( I think I got that right ). So if the OS only sees one 280GB disk it will not handle I/O as well vs having eight 35GB disk arms. Now the actual number of real disks arms will affect how well this concept works. On Wed, Aug 24, 2011 at 1:17 PM, <rob@xxxxxxxxx> wrote:

> I am still not getting why the OS needs to see multiple arms if they are
> all virtual. Instead of one bigger virtual. It's still physically

spread

> across the multiple arms defined either in VIOS or your hosting

partition.

> Is it some weird thing like "let's calculate your journal receiver size
> based on the number of arms you have"?
>
>
> Rob Berendt
> --
> Group Dekko
> Dept 1600
> Mail to: 2505 Dekko Drive
> Garrett, IN 46738
> Ship to: Dock 108
> 6928N 400E
> Kendallville, IN 46755
> http://www.dekko.com
>
>
>
>
>
> From: Kirk Goins<kirkgoins@xxxxxxxxx>
> To: Midrange-L<midrange-l@xxxxxxxxxxxx>
> Date: 08/24/2011 04:12 PM
> Subject: VIOS and Perf Monitoring
> Sent by:midrange-l-bounces@xxxxxxxxxxxx
>
>
>
> I am getting ready to build a system with VIOS as the Hosting OS and

will

> be
> running several IBM i partitions. I know I should use several smaller
> virtual disks vs 1 big one per partition so the IBM i OS wil see

multiple

> disks/arms. So lets say I have 4 IBM i Partitions all on top of VIOS.
> Each
> partition will see 8 35GB drives and lets say there are 24 139GB ( or
> whatever size VIOS wants to call them ) drives available to VIOS to
> allocate
> disk space with. So lots of room but could use more arms. Now I start a
> really disk intensive process on 2 partitions. How can I tell how busy

the

> drives really are at the VIOS level? On a partition with IBM i hosting I
> can
> do WRKDSKSTS on the base IBM i. Just wondering how to approach disk perf
> issues inthe future.
>
> Thanks
>
> --
> Kirk
> --