Re: [OMPI users] Why is the eager limit set to 12K?

2012-05-09 Thread Shamis, Pavel
> > Thanks a lot for the clarification. Do you know if this empirical tests > has been published somehow/somewhere? I think it was published in very early OSU/MVAPICH related papers. Regards, P. > > cheers, Simone > >> >> On May 7, 2012, at 9:25 AM, Simone Pellegrini wrote: >> >>> Hello,

Re: [OMPI users] Why is the eager limit set to 12K?

2012-05-09 Thread Jeff Squyres
On May 9, 2012, at 8:45 AM, Simone Pellegrini wrote: >> I *believe* that this value came out of IB hardware history. I.e., when we >> wrote the openib BTL, some empirical testing showed that 12k was a good >> value. > > Thanks a lot for the clarification. Do you know if this empirical tests

Re: [OMPI users] Why is the eager limit set to 12K?

2012-05-09 Thread Simone Pellegrini
On Tue 08 May 2012 02:53:28 AM CEST, Jeff Squyres (jsquyres) wrote: I *believe* that this value came out of IB hardware history. I.e., when we wrote the openib BTL, some empirical testing showed that 12k was a good value. Thanks a lot for the clarification. Do you know if this empirical

Re: [OMPI users] Why is the eager limit set to 12K?

2012-05-07 Thread Jeff Squyres (jsquyres)
I *believe* that this value came out of IB hardware history. I.e., when we wrote the openib BTL, some empirical testing showed that 12k was a good value. On May 7, 2012, at 9:25 AM, Simone Pellegrini wrote: > Hello, > I have one of those 1M dollar questions I guess, but why the eager limit >

[OMPI users] Why is the eager limit set to 12K?

2012-05-07 Thread Simone Pellegrini
Hello, I have one of those 1M dollar questions I guess, but why the eager limit threshold for Infiniband is set to 12KB by default in OpenMPI? I would like to know where this value comes from. I am not wondering whether this is a good setting for this parameter, but just why this is