Re: VIOS and Perf Monitoring

[Jim Oberholtzer <midrangel@xxxxxxxxxx>]

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
> > >  --