Thanks Ed. I am not running SFS and I understand that VMRM requires the
config file to be under SFS control is this correct?  Also the only
thing that came on the A disk for the VMRMSVM user was the PROFILE EXEC.
I read that there should be a sample config file as well as some other
files on the A disk also, is there another place theses file can be
found? 

 

Thank You,

 

Terry Martin

Lockheed Martin - Information Technology

z/OS & z/VM Systems - Performance and Tuning

Cell - 443 632-4191

Work - 410 786-0386

terry.mar...@cms.hhs.gov <mailto:terry.mar...@cms.hhs.gov> 

 

WFH Tuesdays and Fridays

________________________________

From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On
Behalf Of Ed Neidhardt
Sent: Friday, October 30, 2009 12:19 PM
To: IBMVM@LISTSERV.UARK.EDU
Subject: Re: VMRMSVM - z/VM Resource Manager

 

Terry,

I've been using it for around 10 months now at one of my customers and
it appears to be doing the job. Their environment experiences huge CPU
spikes during it's month end processing (4-6 days of 95-100%, where
normally CPU is around 40%).  They are using Focus to produce a large
number of reports from databases with several million records in each.  

 

Before trying VMRMSVM the operators where busy adjusting relative shares
during month end to keep the VSE nightly batch cycle from running over,
while also trying to keep the Focus machines processing to meet their
deadline.  We tried various combinations of relative and absolute
shares, but were never able to get the right mix to meet everyone's
deadlines.  The problems were: month end started on different days of
the week (each day has it's unique processing), the amount of data being
processed varied by hundred's of thousands records, and the mix of Focus
runs would change (quarter end, year end, etc) 

 

Getting a larger z9 or using capacity on demand (on a monthly basis)
were too costly to do, especially with the much lower utilization during
the rest of the month.

 

Using VMRMSVM to adjust the relative appears to help because both the
VSE and the Focus workloads are getting finished before their deadline.
The operators are no longer allowed to adjust the relative shares and
I'm not getting calls in the night about VSE or Focus jobs being too
slow.   

 

I don't profess to fully understand VMRMSVM, but here are some
observations I've found while using this:

1) Put all your zVM machines under it's control (there are some
exceptions like VMRMSVM, PERFSVM, and there could be others in your
case).  VMRMSVM appears to do a better job balancing when it sees all
the work not just a small group of machines.

 

2) Place each of the heavy CPU machines in their own group. VMRM checks
the CPU run/wait deltas proportion of  all the machines in a group. One
heavy CPU machine in a group will cause the group to exceed it's goals.
VMRM then starts adjusting the relative shares downward for all the
machines in the group, particularly the heavy CPU machine.   With some
of the Focus runs going for 8 hours or more I saw some relative shares
of 1 which was a bit of shock.  I found I needed to have 15-20 groups
altogether with 10 of those being single machine groups

 

3) I used the option of being able to dynamically change configurations.
I did this to reduce the goals for the Focus processing during the
nightly VSE batch work. When the VSE work finishes, I raise the goals
again.

 

4) It's been an iterative process  of setting goals and mixing (or
separating) machines.

 

5) I don't normally see much, if any change in the relative share values
VMRM sets when the z9 is lightly loaded.

 

Ed Neidhardt

Mainline Information Systems, Inc.

770-321-0841 Office

ed.neidha...@mainline.com

 

----- Original Message ----- 

        From: Martin, Terry R. (CMS/CTR) (CTR)
<mailto:terry.mar...@cms.hhs.gov>  

        To: IBMVM@LISTSERV.UARK.EDU 

        Sent: Thursday, October 29, 2009 8:06 PM

        Subject: VMRMSVM - z/VM Resource Manager

         

        Hi,

         

        I am looking at implementing VMRM. I was wondering if you use it
and if it is working as advertised?  I want to mainly use it for
managing the priority of my different workloads running in z/Linux. I am
familiar with the goal concept from WLM on the z/OS side so I understand
the principle behind it but I just wanted to know from those who use it
how it is working. Also any specifics on setting it up in terms of what
to watch out for etc....

         

        Thank You,

         

        Terry Martin

        Lockheed Martin - Information Technology

        z/OS & z/VM Systems - Performance and Tuning

        Cell - 443 632-4191

        Work - 410 786-0386

        terry.mar...@cms.hhs.gov

         

        WFH on Tuesdays and Fridays

         

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