My bad, i forgot btl/tcp is using all the interfaces by default (eth0 *and* ib0)
is eth0 available on all your nodes or just the node running mpirun ? you can try to use a subnet instead of an interface name mpirun --mca btl_tcp_if_include 172.24.44.0/23 ... if you are still facing some issues, you can mpirun ... --mca btl_base_verbose 100 ... in order to collect (lot of) logs Cheers, Gilles On Wed, Aug 16, 2017 at 10:54 PM, Maksym Planeta <mplan...@os.inf.tu-dresden.de> wrote: > Dear Gilles, > > thank you for quick response. > > pml/cm doesn't work at all > > When I use "--mca pml ob1" I still see traffic in /usr/sbin/perfquery, but > the program starts running a lot slower. E. g. ib.C.64 benchmarks runs 33 > seconds in contrast to less than 1. > > I also see many if following warning messages when I use PML ob1: > > [<hostname>:25220] mca_base_component_repository_open: unable to open > mca_coll_hcoll: libmxm.so.2: cannot open shared object file: No such file or > directory (ignored) > > But at least I see traffic on ib0 interface. So I basically achieved the goal > from the original mail. > > Nevertheless I wanted to try avoid IB completely, so I added "--mca > btl_tcp_if_exclude ib0". But no program cannot run and fails with these kinds > of messages: > > > [<hostname>][[42657,1],23][btl_tcp_endpoint.c:649:mca_btl_tcp_endpoint_recv_connect_ack] > received unexpected process identifier [[42657,1],1] > > I see the same message when I also use this flag "--mca btl_tcp_if_include > lo,ib0" > > Here is full command: > > $ mpirun --mca pml ob1 --mca btl self,tcp --mca btl_tcp_if_include lo,ib0 > -np 64 bin/is.C.64 > > I also tried to use "--mca btl_tcp_if_include lo,eth0", but MPI started > complaining with this message: > > [<hostname>][[40797,1],58][btl_tcp_component.c:706:mca_btl_tcp_component_create_instances] > invalid interface "eth0" > > I do have this interface: > > $ ip addr show eth0 > 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen > 1000 > link/ether 08:00:38:3c:4e:65 brd ff:ff:ff:ff:ff:ff > inet 172.24.44.190/23 brd 172.24.45.255 scope global eth0 > inet6 fe80::a00:38ff:fe3c:4e65/64 scope link > valid_lft forever preferred_lft forever > > > Can I tell somehow MPI to use eth0, and not use ib0? > > On 08/16/2017 02:34 PM, Gilles Gouaillardet wrote: >> Hi, >> >> you can try >> mpirun --mca pml ob1 --mca btl tcp,self ... >> >> >> pml/cm has a higher priority than pml/ob1, so if you have a mtl that >> fits your network (such as mtl/mxm), >> then pml/ob1 will be ignored, and the list of allowed/excluded btl >> become insignificant. >> >> Cheers, >> >> Gilles >> >> On Wed, Aug 16, 2017 at 8:57 PM, Maksym Planeta >> <mplan...@os.inf.tu-dresden.de> wrote: >>> Hello, >>> >>> I work with an Infiniband cluster, but I want to force OpenMPI to use >>> specific network interface. >>> >>> I tried to do this for example using mpirun as follows: >>> >>> mpirun --map-by node --mca btl self,tcp -np 16 bin/is.C.16 >>> >>> But counters returned by /usr/sbin/perfquery still keep showing that >>> transmission happens over ibverbs. >>> >>> There is an iboib module on a machine, but counters there (ip -s link) >>> indicate that the ib0 interface is not used. >>> >>> Could you help me to figure out how to properly tell OpenMPI not to use >>> ibverbs? >>> >>> I tried with Open MPI 2.1.0 and 1.10.2, but saw no difference in behavior. >>> >>> >>> -- >>> Regards, >>> Maksym Planeta >>> >>> >>> _______________________________________________ >>> users mailing list >>> users@lists.open-mpi.org >>> https://lists.open-mpi.org/mailman/listinfo/users >> _______________________________________________ >> users mailing list >> users@lists.open-mpi.org >> https://lists.open-mpi.org/mailman/listinfo/users >> > > -- > Regards, > Maksym Planeta > > > _______________________________________________ > users mailing list > users@lists.open-mpi.org > https://lists.open-mpi.org/mailman/listinfo/users _______________________________________________ users mailing list users@lists.open-mpi.org https://lists.open-mpi.org/mailman/listinfo/users