yes, that is clearly suboptimal. the optimal option is something like -bind-to hwthreads (I am afk so I cannot confirm this)
Cheers, Gilles On Sunday, May 24, 2015, XingFENG <xingf...@cse.unsw.edu.au> wrote: > Hi, Gilles, > > Thanks very much for your respond. But if I oversubscribe, would the > performance be influenced? > > On Sun, May 24, 2015 at 7:24 PM, Gilles Gouaillardet < > gilles.gouaillar...@gmail.com > <javascript:_e(%7B%7D,'cvml','gilles.gouaillar...@gmail.com');>> wrote: > >> Hi Xing, >> >> iirc, open MPI default behavior is to bind to cores (vs hyperthreads), >> hence the error message. >> >> I cannot remember the option to bind to threads, but you can mpirun >> --oversubscribe if you are currently stuck >> >> Cheers, >> >> Gilles >> >> >> On Sunday, May 24, 2015, XingFENG <xingf...@cse.unsw.edu.au >> <javascript:_e(%7B%7D,'cvml','xingf...@cse.unsw.edu.au');>> wrote: >> >>> Hi, OPENMPI users, >>> >>> I have met some problem while doing experiments on Amazon EC2. I have >>> chosen instance type r3.2xlarge. As amazon claimed, it has 8 vcpu. Each >>> vCPU is a hyperthread of an Intel Xeon core for M3, C4, C3, R3, HS1, G2, >>> I2, and D2. (from *https://aws.amazon.com/ec2/instance-types/ >>> <https://aws.amazon.com/ec2/instance-types/>)* >>> >>> However, when I try to run experiments on 4 machines, each with 8 slots. >>> OPENMPI reminds me that I am oversubscribing. >>> >>> Does anyone know the reason? Thanks in advance! >>> >>> >>> -- >>> Best Regards. >>> --- >>> Xing FENG >>> PhD Candidate >>> Database Research Group >>> >>> School of Computer Science and Engineering >>> University of New South Wales >>> NSW 2052, Sydney >>> >>> Phone: (+61) 413 857 288 >>> >> >> _______________________________________________ >> users mailing list >> us...@open-mpi.org <javascript:_e(%7B%7D,'cvml','us...@open-mpi.org');> >> Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users >> Link to this post: >> http://www.open-mpi.org/community/lists/users/2015/05/26909.php >> > > > > -- > Best Regards. > --- > Xing FENG > PhD Candidate > Database Research Group > > School of Computer Science and Engineering > University of New South Wales > NSW 2052, Sydney > > Phone: (+61) 413 857 288 >
