The MPI_Win_flush/flush_all calls are part of the passive-target synchronization model. You must first lock the target (or all targets) before performing any RMA or flush operations.
-Nathan Hjelm
HPC-5, LANL
On Mon, Dec 14, 2015 at 09:58:06PM +0000, Palmer, Bruce J wrote:
> I'm trying to get some code working using request-based RMA (MPI_Rput,
> MPI_Rget, MPI_Raccumulate). My understanding of the MPI 3.0 standard is
> that after calling MPI_Wait on the request handle, the local buffers
> should be safe to use. On calling MPI_Win_flush_all on the window used for
> RMA operations, all operations should be completed on the remote
> processor. Based on this, I would expect that the following program should
> work:
>
>
>
> #include <mpi.h>
>
>
>
> int main(int argc, char *argv[])
>
> {
>
> int bytes = 4096;
>
> MPI_Win win;
>
> void *buf;
>
>
>
> MPI_Init(&argc, &argv);
>
>
>
> MPI_Alloc_mem(bytes,MPI_INFO_NULL, &win);
>
> MPI_Win_create(buf,bytes,1,MPI_INFO_NULL,MPI_COMM_WORLD,&win);
>
> MPI_Win_flush_all(win);
>
>
>
> MPI_Win_free(&win);
>
> MPI_Finalize();
>
> return(0);
>
> }
>
>
>
> However, with openmpi-1.8.3 I'm seeing a crash
>
>
>
> [node302:3689] *** An error occurred in MPI_Win_flush_all
>
> [node302:3689] *** reported by process [2431516673,0]
>
> [node302:3689] *** on win rdma window 3
>
> [node302:3689] *** MPI_ERR_RMA_SYNC: error executing rma sync
>
> [node302:3689] *** MPI_ERRORS_ARE_FATAL (processes in this win will now
> abort,
>
> [node302:3689] *** and potentially your MPI job)
>
>
>
> I'm seeing similar failures for mvapich2-2.1 and mpich-3.2. Does anyone
> know if this stuff is suppose to work? I've had pretty good luck using the
> original RMA calls (MPI_Put, MPI_Get and MPI_Accumulate) with
> MPI_Lock/MPI_Unlock but the request-based calls are mostly a complete
> failure.
>
>
>
> Bruce Palmer
> _______________________________________________
> users mailing list
> 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/2015/12/28158.php
pgp1GKy6R6oMq.pgp
Description: PGP signature
