On 19/09/13 10:12, Andrew Lahiff wrote:
> Hi,
>
> For the record, for the new batch system at RAL we have multicore queues
> on our CREAM CEs (currently configured to use 8 cores). However, on the
> ARC CEs jobs can request exactly how many cores (and how much memory)
> they need rather than having to use a specific queue.
I believe it is perfectly possible to do this with CREAM too (though I'm
not sure we have it set up on all CEs.
IIRC, when I asked the experiments why this wasn't sufficient and they
wanted to auto discover how big the slot they had got was, it was
because on a 12 core node, if you have jobs requesting 8 slots, they may
actually end up on a 12 slot machine - and if they know this they can
make use of the extra slots they discover they have.
> This is how both
> ATLAS and CMS are running multicore jobs at RAL now. Condor is then
> responsible for scheduling the mix of single and multicore jobs.
Chris
>
> Regards,
> Andrew.
>
> -----Original Message-----
> From: Testbed Support for GridPP member institutes [mailto:[log in to unmask]] On Behalf Of Alessandra Forti
> Sent: 19 September 2013 09:57
> To: [log in to unmask]
> Subject: Re: Technical Meetings
>
> Well that's for testing. If it goes in production it will be more than one node and most of the things that are keeping this back are operational i.e. how not to waste resources and how to do the accounting if a job requests a certain number of CPU or the whole node.
>
> cheers
> alessandra
>
> On 18/09/2013 18:18, Christopher J. Walker wrote:
>> On 18/09/13 17:22, David Colling wrote:
>>> Hi Alessandra,
>>>
>>> Yes they are indeeedee. I only know of bits and pieces in the LHC
>>> world but do know, for example, that our T2K colleagues make
>>> extensive use of them. The Imperial T2K people code and debug locally
>>> and then run on the RAL resources. This is proving so successful that
>>> we are considering adding a bigger node - perhaps to the GridPP
>>> cloud so that others could use it via OpenStack. These are at the
>>> *ideas* stage at the moment, but if we did would there be any takers
>>> or would we have just thrown away a chunk of money (or rather given
>>> it to T2K as I am sure that they would use them)?
>>>
>>> I guess that the question is what should GridPP be doing about this?
>>> I don't see it as our place to fund development in the individual
>>> experiments but should we be acting as a conduit for best practise?
>>> Organising Goofit tutorials? Interacting with EGI as Stephen suggests?
>>> What else? Is there a focus that we can develop with very little money?
>>>
>>> I think that these are questions for next Tuesday rather than Friday
>>> but I will add a specific discussion to the discussion agenda for this.
>> QMUL now has a single node MPI queue - Dan has more details. What more
>> does one need?
>>
>> Chris
>>
>>> Best,
>>> david
>>>
>>> On 18/09/13 14:41, Alessandra Forti wrote:
>>>> Hi,
>>>>
>>>> multicore should become a reality at the end of LS1. We should
>>>> definitely have it as an activity.
>>>>
>>>> cheers
>>>> alessandra
>>>>
>>>> On 18/09/2013 14:12, David Colling wrote:
>>>>> Hi,
>>>>>
>>>>> I am just drawing up an agenda and is it worth having an item on
>>>>> FTS3 (from Andrew L.)?
>>>>>
>>>>> Also the many and multicore activity. Is somebody able to describe
>>>>> what has been happening in these two areas? Is this something that
>>>>> we want to have as an activity in GridPP5?
>>>>>
>>>>> Best,
>>>>> david
>>>>
>
>
> --
> Facts aren't facts if they come from the wrong people. (Paul Krugman)
>
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