> -----Original Message-----
> From: Arnau Bria [mailto:[email protected]]
> Sent: Wednesday, 4 March 2009 2:21 AM
> To: [email protected]
> Subject: [Mauiusers] DEDICATEDPS vs DEDICATEDPES
> 
> Hi all,
> 
> Could someone help me to undestand teh diff bewteen DEDICATEDPES and
> DEDICATEDDPS?
> processor-equivalent second means normalized cpu time?
> 
> TIA,
> Arnau

Hi Arnau,

PE is a measure of how many processors a job is preventing others from 
accessing.  Lets say you have a cluster of dual socket, 4 core machines with 
16GB per node.

A job that requests 1 core and 8GB of memory is effectively using half of a 
node (if we expect most/average jobs to request about 2GB of memory per core 
requested) so has a PE count of 4.
A job that requests 16GB is effectively stopping any other jobs from running on 
a node so PE=8

The concept breaks down on a system which doesn't have highly uniform nodes.

>From 
>http://www.clusterresources.com/products/maui/docs/5.1.2priorityfactors.shtml
: The final resource component, PE, represents 'Processor Equivalents'.  This 
component can be viewed as a processor-weighted maximum 'percentage of total 
resources' factor.  For example, if a job requested 25% of the processors and 
50% of the total memory on a 128 processor O2K system, it would have a PE value 
of MAX(25,50) * 128, or 64.  The concept of PE's may be a little awkward to 
grasp initially but it is a highly effective metric in shared resource systems.

-- Gareth
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