Thanks Jeffrey, I understand, can you please guide me to such paper that give more accurate estimation for the MPI_Bcast.
--- On Wed, 4/4/12, Jeffrey Squyres <jsquyres_at_[hidden]> wrote:
From: Jeffrey Squyres <jsquyres_at_[hidden]>
Subject: Re: [OMPI users] Need Performance estimation of MPI_Bcast
To: "Open MPI Users" <users_at_[hidden]>
Date: Wednesday, April 4, 2012, 4:35 PM
It's a bit more complicated than that; there are many factors involved:
- how many peer MPI processes are involved in the broadcast
- how many of those peers are local (and will likely communicate via shared memory, not a network device) and how many are remote
- what broadcast algorithm is used (there are many)
So the simplistic logp model won't help you here -- you'll need to be more complicated, and/or dig into the academic papers on these kinds of things.
On Apr 4, 2012, at 9:11 AM, anas trad wrote:
> HiÂ EnvoyÃ© ,
> Thanks for the reply but I want to estimate the time of executing MPI_Bcast function by mathmatics. I found that we can achieve this by using LogGP model with this equation:
> T = ceil(log2p) . (L + 2 Â· o + (n â 1) Â· G
> but that does not give good accuracy for time evaluation.
> --- On Wed, 4/4/12, AurÃ©lien Bouteiller <bouteill_at_[hidden]> wrote:
> From: AurÃ©lien Bouteiller <bouteill_at_[hidden]>
> Subject: Re: [OMPI users] Need Performance estimation of MPI_Bcast
> To: "Open MPI Users" <users_at_[hidden]>
> Cc: "users_at_[hidden]" <users_at_[hidden]>
> Date: Wednesday, April 4, 2012, 3:50 PM
> You can use the intel mpi benchmark, or skampi. These two programs are designed to evaluate Moi performance.
> EnvoyÃ© de mon iPad
> Le 2012-04-04 Ã 08:46, anas trad <tradat84_at_[hidden]> a Ã©crit :
>> Hi all,
>> I need to know the time estimation of executing MPI_Bcast function on Neolith Cluster. Please, can anyone show me how to achieve that.
>> users mailing list
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