i opened #4610 https://svn.open-mpi.org/trac/ompi/ticket/4610 and attached a patch for the v1.8 branch
i ran several tests from the intel_tests test suite and did not observe any regression. please note there are still issues when running with --mca btl scif,vader,self this might be an other issue, i will investigate more next week Gilles On 2014/05/09 18:08, Gilles Gouaillardet wrote: > I ran some more investigations with --mca btl scif,self > > i found that the previous patch i posted was complete crap and i > apologize for it. > > on a brighter side, and imho, the issue only occurs if fragments are > received (and then processed) out of order. > /* i did not observe this with the tcp btl, but i always see that with > the scif btl, i guess this can be observed too > with openib+RDMA */ > > in this case only, opal_convertor_generic_simple_position(...) is > invoked and does not set the pConvertor->pStack > as expected by r31496 > > i will run some more tests from now > > Gilles > > On 2014/05/08 2:23, George Bosilca wrote: >> Strange. The outcome and the timing of this issue seems to highlight a link >> with the other datatype-related issue you reported earlier, and as suggested >> by Ralph with Gilles scif+vader issue. >> >> Generally speaking, the mechanism used to split the data in the case of >> multiple BTLs, is identical to the one used to split the data in fragments. >> So, if the culprit is in the splitting logic, one might see some weirdness >> as soon as we force the exclusive usage of the send protocol, with an >> unconventional fragment size. >> >> In other words using the following flags “—mca btl tcp,self —mca >> btl_tcp_flags 3 —mca btl_tcp_rndv_eager_limit 23 —mca btl_tcp_eager_limit 23 >> —mca btl_tcp_max_send_size 23” should always transfer wrong data, even when >> only one single BTL is in play. >> >> George. >> >> On May 7, 2014, at 13:11 , Rolf vandeVaart <rvandeva...@nvidia.com> wrote: >> >>> OK. So, I investigated a little more. I only see the issue when I am >>> running with multiple ports enabled such that I have two openib BTLs >>> instantiated. In addition, large message RDMA has to be enabled. If those >>> conditions are not met, then I do not see the problem. For example: >>> FAILS: >>> Ø mpirun –np 2 –host host1,host2 –mca btl_openib_if_include >>> mlx5_0:1,mlx5_0:2 –mca btl_openib_flags 3 MPI_Isend_ator_c >>> PASS: >>> Ø mpirun –np 2 –host host1,host2 –mca btl_openib_if_include mlx5_0:1 –mca >>> btl_openib_flags 3 MPI_Isend_ator_c >>> Ø mpirun –np 2 –host host1,host2 –mca >>> btl_openib_if_include_mlx5:0:1,mlx5_0:2 –mca btl_openib_flags 1 >>> MPI_Isend_ator_c >>> >>> So we must have some type of issue when we break up the message between the >>> two openib BTLs. Maybe someone else can confirm my observations? >>> I was testing against the latest trunk. >>>