On Tue, Dec 27, 2011 at 11:25 AM, Mike Haudenschild <m...@longsight.com> wrote:
> Good morning --
>
> I have two questions regarding computer settings in VCL -- the "RAM," "No.
> Processors," and "Processors Speed (MHz)" settings when creating computers,
> or editing computer information from the Manage Computers tab.
>
> Note that I'm using VCL exclusively with ESXi 4.1, manually installed (no
> xCAT).
>
>   1. Am I correct that these settings are irrelevant for my VMWare host
>   computer because ESXi was manually installed (i.e. not provisioned via
>   xCAT)?

Yes.  The VM host hardware values aren't currently used.  They will be
used at some point in the future to determine host
capacity/utilization in order to improve the scheduling of
reservations.  It's not important to set these accurately because the
code will automatically retrieve the values from the host and update
the database.

>   2. I've watched the VCL bootcamp videos from NCSU this past summer, and
>   there was a comment that these settings apply only to virtual machines --
>   specifically, to match requested images up with available VMs.  However,
>   end-user reservations are getting hardware based upon what was configured
>   for the original image, not what I've subsequently specified when adding
>   individual VM "computers" or "slots."  For example, the base image was
>   created with a 2GHz processor and 512 MB RAM.  When a reservation is made
>   using a VM that I've set as having only 256MB RAM and a 1GHZ processor,
>   those settings seem to be ignored -- the original hardware settings from
>   the image (2GHz, 512MB RAM) are assigned to the VM slot.

The VM hardware settings are used in 2 ways:

1) By the scheduler to locate a computer that meets the requirements
set in the image profile.  This is the same for VMs and bare-metal
computers.  If your VM is set to 256 MB and your image is set to 512
MB, reservations for that image shouldn't be scheduled on that VM.  Is
this what you're seeing?  If so then there's a problem with the
scheduling code.

2) By the provisioning module to construct a VM.  The RAM and CPU
values for the image are normally used.  If your image is set to 1 GB
RAM and your computer is set to 2 GB, the VM will have 1 GB.

There are a few caveats.  There is a hard-coded minimum RAM value of
512 MB.  This is done to prevent unusable VMs from being created if
the image profile RAM setting is set to 0 or a very low value.  If
your computer is set to 1 GB and your image is set to 256 MB, the VM
will be assigned 512 MB.  There are other RAM minimums higher than 512
MB depending on the OS of the image being loaded.  I don't recall all
of them off hand but for example I believe 32-bit Windows 7 is 1 GB,
etc.

-Andy

> Thanks to everyone on the list -- you've all been so helpful as I'm getting
> to know VCL.
>
> Regards,
> Mike
>
> --
> *Mike Haudenschild*
> Education Systems Manager
> Longsight Group
> (740) 599-5005 x809
> m...@longsight.com
> www.longsight.com

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