> I have one final question, which is about fairshare, does anyone
> understand the difference between DEDICATEDPS and DEDICATEDPES in
> maui? I want to make sure that fairshares are calculated based on
> wallclock times, not on cpu consumption times. The maui manual
> describes FSPOLICY (http://tinyurl.com/cjgpba), but doesn't really
> explain which setting does what.
My understanding is that DEDICATEDPS just measures CPU usage, whereas
DEDICATEDPES measures 'Processor Equivalent' usage, which takes into account the
usage of other resources (e.g. memory) and converts this into a measure of how
many processors the job is effectively occupying (in the sense of 'using or
indirectly preventing other jobs using').
E.g. if a job is using 1 core and 8GB of memory on an 8-core 16GB system, it has
a PE of 4 as even though it's only using 1 of 8 cores, it's using half the
memory and so half the node. Hence with DEDICATEDPES it'll be treated as taking
up four times the resources it would have with DEDICATEDPS.
With both, the usage is based on what the scheduler has assigned to the job, not
what the job has consumed.
Robert Fay [log in to unmask]
System Administrator office: 220
High Energy Physics Division tel (int): 43396
Oliver Lodge Laboratory tel (ext): +44 (0)151 794 3396
University of Liverpool http://www.liv.ac.uk/physics/hep/