[Gate-users] Parallel simulations and hardware specifications

[Alex Vergara Gil]

Dear Matthieu

"What is the official Gate repository ?"
The Official Gate Repository is https://github.com/OpenGATE/Gate

"What you meant is that with the MT mode set up, it is possible to
fully use an Intel Xeon Phi card type by using all its threads, with
no need for a cluster architecture ?"
Yes, you fully understand

Regards
Alex

2015-04-13 4:46 GMT-04:00, Matthieu Dondey <m.dondey at gmail.com>:
> Dear Alex,
>
> Thank you very much for this precious thread.
>
> I didn't fully understand "Once we finally set MT mode it can be integrated
> into official Gate repository to run, for instance, in an Intel Xeon Phi
> card without further requirements."
>
> What is the official Gate repository ? What you meant is that with the MT
> mode set up, it is possible to fully use an Intel Xeon Phi card type by
> using all its threads, with no need for a cluster architecture ?
>
> Regards,
>
> Matthieu
>
> 2015-04-10 19:08 GMT+02:00 Alex Vergara Gil <alexvergaragil at gmail.com>:
>
>> Dear Matthieu
>>
>> You may want to read the thread "Adding G4MTRunManager support to
>> Gate", on it we explain our progress to make Gate running in
>> Multithread mode and you are also welcome to contribute to the git
>> repository in https://github.com/BishopWolf/Gate. Once we finally set
>> MT mode it can be integrated into official Gate repository to run, for
>> instance, in an Intel Xeon Phi card without further requirements.
>>
>> Regards
>> Alex
>>
>> 2015-04-10 10:01 GMT-04:00, Matthieu Dondey <m.dondey at gmail.com>:
>> > ​​
>> >
>> > Dear Gaters,
>> >
>> >
>> >
>> > We expect to soon have some funds in our lab to buy a simulation
>> > workstation and one of its purposes will be Gate Monte Carlo
>> > simulations.
>> >
>> > I’ve tried to gather what the important hardware specifications are but
>> I’d
>> > like to have advice from people who are already performing parallel
>> > simulations on multi-thread workstation or clusters.
>> >
>> > My first question is about methodology:
>> >
>> > To split a simulation into several jobs when using a multi-core
>> > computer,
>> > is the process the same as the one described in the Users guide -
>> Parallel
>> > Computing -> How to use Gate on a cluster?
>> >
>> > Next, is it really beneficial to use GPU + CPU instead of CPUs alone?
>> > Is
>> > the Nvidia CUDA technology well adapted to Gate simulations and what
>> > are
>> > its benefits and downsides?
>> >
>> > Lastly, I’ve read in the Users Guide:
>> >
>> > *In planning simulation time, it is important to be aware that Gate
>> > simulations currently seem to benefit only from the addition of
>> > physical
>> > CPUs. A computer with 8 hyper-threaded physical CPU cores (16 logical
>> CPUs)
>> > will have the same computational efficiency if 8 processes are run
>> > simultaneously as it would with 16 simultaneous processes.*
>> >
>> >
>> >
>> > Can someone confirm and explain why it is impossible to use logical
>> threads
>> > with Gate (“seem to benefit” doesn’t seem realy categorical)? Is it an
>> > issue which will be fixed in next versions of GATE? Is it a Geant4
>> specific
>> > problem? Or is it possible to exploit logical threads on Geant4?
>> >
>> >
>> > Any help will be greatly appreciated and I'd be very grateful about any
>> > other advice on hardware specifications (RAM usage, important spec of
>> > processors, benefit of a SSD, etc.)
>> >
>> >
>> > Cheers,
>> >
>> >
>> > Matthieu
>> >
>>
>