• Xin Zhao's avatar
    Adding reduce-scatter based algorithm in MPI_Win_fence. · 97569a1a
    Xin Zhao authored
    
    
    In this patch, we add a reduce-scatter based algorithm in
    MPI_Win_fence, which is triggered when number of processes
    is at a small / medium value. When this algorithm is being
    used, memory usage is O(P), but the ending FENCE only needs
    to wait for local completion but does not need to wait for
    remote completion. When number of processes is large, we
    switch FENCE to the original barrier based algorithm, which
    has O(1) memory usage, but needs to wait for the remote
    completion in the ending FENCE.
    Signed-off-by: Pavan Balaji's avatarPavan Balaji <balaji@anl.gov>
    97569a1a
ch3u_rma_sync.c 74 KB