Mapping and binding is related to so called process affinity. It's a bit difficult for me to explain ...
So please see this URL below(especially the first half part of it - from 1 to 20 pages): http://www.slideshare.net/jsquyres/open-mpi-explorations-in-process-affinity-eurompi13-presentation Although these slides by Jeff are the explanation for LAMA, which is another mapping system installed in the openmpi-1.7 series, I guess you can easily understand what is mapping and binding in general terms. Tetsuya > Thank you Tetsuya - it worked. > > Btw. what's the difference between mapping and binding? I think I am bit confused here. > > Thank you, > Saliya > > > On Thu, Mar 27, 2014 at 4:19 AM, <tmish...@jcity.maeda.co.jp>wrote: > > > Hi Saliya, > > What you want to do is map-by node. So please try below: > > -np 2 --map-by node:pe=4 --bind-to core > > You might not need to add --bind-to core, because it's default binding. > > Tetsuya > > > Hi, > > > > I see in v.1.7.5rc5 --cpus-per-proc is deprecated and is advised to > replace by --map-by <obj>:PE=N. > > I've tried this but I couldn't get the expected allocation of procs. > > > > For example I was running 2 procs on 2 nodes each with 2 sockets where a > socket has 4 cores. I wanted 1 proc per node and bound to all cores in one > of the sockets. I could get this by using > > > > --bind-to core: --map-by ppr:1:node --cpus-per-proc 4 -np 2 > > > > Then it'll show bindings as > > > > [i51:32274] MCW rank 0 bound to socket 0[core 0[hwt 0]], socket 0[core 1 > [hwt 0]], socket 0[core 2[hwt 0]], socket 0[core 3[hwt 0]]: > [B/B/B/B][./././.] > > [i52:31765] MCW rank 1 bound to socket 0[core 0[hwt 0]], socket 0[core 1 > [hwt 0]], socket 0[core 2[hwt 0]], socket 0[core 3[hwt 0]]: > [B/B/B/B][./././.] > > > > > > Is there a better way without using -cpus-per-proc as suggested to get > the same effect? > > > > Thank you, > > Saliya > > > > > > > > -- > > Saliya Ekanayake esal...@gmail.com > > Cell 812-391-4914 Home 812-961-6383 > > http://saliya.org_______________________________________________ > > users mailing list > > users@open-mpi.orghttp://www.open-mpi.org/mailman/listinfo.cgi/users > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > -- > Saliya Ekanayake esal...@gmail.com > Cell 812-391-4914 Home 812-961-6383 > http://saliya.org_______________________________________________ > users mailing list > users@open-mpi.orghttp://www.open-mpi.org/mailman/listinfo.cgi/users
