I certainly did not want to cause confusion - this is why I said " There is
actually more science..."  I was passing on what we learned through trial,
error and then a phone call.  And blast it, you are indeed correct Kris.

On a system with 11 IFLs and a 2 vcpu guest that we needed to cap at 25%, we
had to set its share as SET SHARE RELATIVE 200 ABSOLUTE 2.3% LIMITHARD.
This is the only way we could successfully get the server to not go over 25%
cpu total.

In our case, the linux guests are all multi-processor apps and none are
multi-vcpu uniprocessor apps so the behavior was as expected, the apps got
up to 25% (and not 12.5% if they were uniprocessing)

The answer is I guess "It Depends" since you will really need to know your
applications and how they run in order to set the SHARE the way you really
need it.  I was trying to keep it "simple" - ha!

Jim

On 8/3/07, Kris Buelens <[EMAIL PROTECTED]> wrote:
>
> Jim, I'd say your append can introduce confusion.
>
> The vcpus still count for absolute shares.  But, indeed, the number of
> real CPUs come into account: the % written on the SET SHAER command is
> expressed as a % of the whole system.
> If you have 10 CPU's, a SET SHARE ABS 5% LIMITHARD means that a
> uniprocessor guest can consume 50% of one CPU.  If the guest has two virtual
> processors, each one can consume 25% at most.  This is very important if
> this guest would run one heavy uniprocessing task, this task will have a
> hard time to get more than 25% of a CPU.  We learned this the hard way when
> installing a 6 engine 9672 ages ago (our heavy process was a VM DB2 server)

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