k..Thank you all. That has solved.
On Fri, Nov 4, 2016 at 8:24 PM, r...@open-mpi.org <r...@open-mpi.org> wrote: > All true - but I reiterate. The source of the problem is that the > "--map-by node” on the cmd line must come *before* your application. > Otherwise, none of these suggestions will help. > > > On Nov 4, 2016, at 6:52 AM, Jeff Squyres (jsquyres) <jsquy...@cisco.com> > wrote: > > > > In your case, using slots or --npernode or --map-by node will result in > the same distribution of processes because you're only launching 1 process > per node (a.k.a. "1ppn"). > > > > They have more pronounced differences when you're launching more than > 1ppn. > > > > Let's take a step back: you should know that Open MPI uses 3 phases to > plan out how it will launch your MPI job: > > > > 1. Mapping: where each process will go > > 2. Ordering: after mapping, how each process will be numbered (this > translates to rank ordering MPI_COMM_WORLD) > > 3. Binding: binding processes to processors > > > > #3 is not pertinent to this conversation, so I'll leave it out of my > discussion below. > > > > We're mostly talking about #1 here. Let's look at each of the three > options mentioned in this thread individually. In each of the items below, > I assume you are using *just* that option, and *neither of the other 2 > options*: > > > > 1. slots: this tells Open MPI the maximum number of processes that can > be placed on a server before it is considered to be "oversubscribed" (and > Open MPI won't let you oversubscribe by default). > > > > So when you say "slots=1", you're basically telling Open MPI to launch 1 > process per node and then to move on to the next node. If you said > "slots=3", then Open MPI would launch up to 3 processes per node before > moving on to the next (until the total np processes were launched). > > > > *** Be aware that we have changed the hostfile default value of slots > (i.e., what number of slots to use if it is not specified in the hostfile) > in different versions of Open MPI. When using hostfiles, in most cases, > you'll see either a default value of 1 or the total number of cores on the > node. > > > > 2. --map-by node: in this case, Open MPI will map out processes round > robin by *node* instead of its default by *core*. Hence, even if you had > "slots=3" and -np 9, Open MPI would first put a process on node A, then put > a process on node B, then a process on node C, and then loop back to > putting a 2nd process on node A, ...etc. > > > > 3. --npernode: in this case, you're telling Open MPI how many processes > to put on each node before moving on to the next node. E.g., if you > "mpirun -np 9 ..." (and assuming you have >=3 slots per node), Open MPI > will put 3 processes on each node before moving on to the next node. > > > > With the default MPI_COMM_WORLD rank ordering, the practical difference > in these three options is: > > > > Case 1: > > > > $ cat hostfile > > a slots=3 > > b slots=3 > > c slots=3 > > $ mpirun --hostfile hostfile -np 9 my_mpi_executable > > > > In this case, you'll end up with MCW ranks 0-2 on a, 3-5 on b, and 6-8 > on c. > > > > Case 2: > > > > # Setting an arbitrarily large number of slots per host just to be > explicitly clear for this example > > $ cat hostfile > > a slots=20 > > b slots=20 > > c slots=20 > > $ mpirun --hostfile hostfile -np 9 --map-by node my_mpi_executable > > > > In this case, you'll end up with MCW ranks 0,3,6 on a, 1,4,7 on b, and > 2,5,8 on c. > > > > Case 3: > > > > # Setting an arbitrarily large number of slots per host just to be > explicitly clear for this example > > $ cat hostfile > > a slots=20 > > b slots=20 > > c slots=20 > > $ mpirun --hostfile hostfile -np 9 --npernode 3 my_mpi_executable > > > > In this case, you'll end up with the same distribution / rank ordering > as case #1, but you'll still have 17 more slots you could have used. > > > > There are lots of variations on this, too, because these mpirun options > (and many others) can be used in conjunction with each other. But that > gets pretty esoteric pretty quickly; most users don't have a need for such > complexity. > > > > > > > >> On Nov 4, 2016, at 8:57 AM, Bennet Fauber <ben...@umich.edu> wrote: > >> > >> Mahesh, > >> > >> Depending what you are trying to accomplish, might using the mpirun > option > >> > >> -pernode -o- --pernode > >> > >> work for you? That requests that only one process be spawned per > >> available node. > >> > >> We generally use this for hybrid codes, where the single process will > >> spawn threads to the remaining processors. > >> > >> Just a thought, -- bennet > >> > >> > >> > >> > >> > >> On Fri, Nov 4, 2016 at 8:39 AM, Mahesh Nanavalla > >> <mahesh.nanavalla...@gmail.com> wrote: > >>> s........... > >>> > >>> Thanks for responding me. > >>> i have solved that as below by limiting slots in hostfile > >>> > >>> root@OpenWrt:~# cat myhostfile > >>> root@10.73.145.1 slots=1 > >>> root@10.74.25.1 slots=1 > >>> root@10.74.46.1 slots=1 > >>> > >>> > >>> I want the difference between the slots limiting in myhostfile and > runnig > >>> --map-by node. > >>> > >>> I am awaiting for your reply. > >>> > >>> On Fri, Nov 4, 2016 at 5:25 PM, r...@open-mpi.org <r...@open-mpi.org> > wrote: > >>>> > >>>> My apologies - the problem is that you list the option _after_ your > >>>> executable name, and so we think it is an argument for your > executable. You > >>>> need to list the option _before_ your executable on the cmd line > >>>> > >>>> > >>>> On Nov 4, 2016, at 4:44 AM, Mahesh Nanavalla > >>>> <mahesh.nanavalla...@gmail.com> wrote: > >>>> > >>>> Thanks for reply, > >>>> > >>>> But,with space also not running on one process one each node > >>>> > >>>> root@OpenWrt:~# /usr/bin/mpirun --allow-run-as-root -np 3 --hostfile > >>>> myhostfile /usr/bin/openmpiWiFiBulb --map-by node > >>>> > >>>> And > >>>> > >>>> If use like this it,s working fine(running one process on each node) > >>>> /root@OpenWrt:~#/usr/bin/mpirun --allow-run-as-root -np 3 --host > >>>> root@10.74.25.1,root@10.74.46.1,root@10.73.145.1 > /usr/bin/openmpiWiFiBulb > >>>> > >>>> But,i want use hostfile only.. > >>>> kindly help me..... > >>>> > >>>> > >>>> On Fri, Nov 4, 2016 at 5:00 PM, r...@open-mpi.org <r...@open-mpi.org> > wrote: > >>>>> > >>>>> you mistyped the option - it is “--map-by node”. Note the space > between > >>>>> “by” and “node” - you had typed it with a “-“ instead of a “space” > >>>>> > >>>>> > >>>>> On Nov 4, 2016, at 4:28 AM, Mahesh Nanavalla > >>>>> <mahesh.nanavalla...@gmail.com> wrote: > >>>>> > >>>>> Hi all, > >>>>> > >>>>> I am using openmpi-1.10.3,using quad core processor(node). > >>>>> > >>>>> I am running 3 processes on three nodes(provided by hostfile) each > node > >>>>> process is limited by --map-by-node as below > >>>>> > >>>>> root@OpenWrt:~# /usr/bin/mpirun --allow-run-as-root -np 3 --hostfile > >>>>> myhostfile /usr/bin/openmpiWiFiBulb --map-by-node > >>>>> > >>>>> root@OpenWrt:~# cat myhostfile > >>>>> root@10.73.145.1:1 > >>>>> root@10.74.25.1:1 > >>>>> root@10.74.46.1:1 > >>>>> > >>>>> > >>>>> Problem is 3 process running on one node.it's not mapping one > process by > >>>>> node. > >>>>> > >>>>> is there any library used to run like above.if yes please tell me > that . > >>>>> > >>>>> Kindly help me where am doing wrong... > >>>>> > >>>>> Thanks&Regards, > >>>>> Mahesh N > >>>>> > >>>>> _______________________________________________ > >>>>> users mailing list > >>>>> users@lists.open-mpi.org > >>>>> https://rfd.newmexicoconsortium.org/mailman/listinfo/users > >>>>> > >>>>> > >>>>> > >>>>> _______________________________________________ > >>>>> users mailing list > >>>>> users@lists.open-mpi.org > >>>>> https://rfd.newmexicoconsortium.org/mailman/listinfo/users > >>>> > >>>> > >>>> _______________________________________________ > >>>> users mailing list > >>>> users@lists.open-mpi.org > >>>> https://rfd.newmexicoconsortium.org/mailman/listinfo/users > >>>> > >>>> > >>>> > >>>> _______________________________________________ > >>>> users mailing list > >>>> users@lists.open-mpi.org > >>>> https://rfd.newmexicoconsortium.org/mailman/listinfo/users > >>> > >>> > >>> > >>> _______________________________________________ > >>> users mailing list > >>> users@lists.open-mpi.org > >>> https://rfd.newmexicoconsortium.org/mailman/listinfo/users > >> _______________________________________________ > >> users mailing list > >> users@lists.open-mpi.org > >> https://rfd.newmexicoconsortium.org/mailman/listinfo/users > > > > > > -- > > Jeff Squyres > > jsquy...@cisco.com > > For corporate legal information go to: http://www.cisco.com/web/ > about/doing_business/legal/cri/ > > > > _______________________________________________ > > users mailing list > > users@lists.open-mpi.org > > https://rfd.newmexicoconsortium.org/mailman/listinfo/users > > _______________________________________________ > users mailing list > users@lists.open-mpi.org > https://rfd.newmexicoconsortium.org/mailman/listinfo/users >
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