Hello, I have a general question about the best way to implement an openmpi application, i.e the design of the application.
A machine (I call it the "server") should send to a cluster containing a lot of processors (the "clients") regularly task to do (byte buffers from very various size). The server should send to each client a different buffer, then wait for each client answers (buffer sent by each client after some processing), and retrieve the result data. First I made something looking like this. On the server side: Send sequentially to each client buffers using MPI_Send. On each client side: loop which waits a buffer using MPI_Recv, then process the buffer and sends the result using MPI_Send This is really not efficient because a lot of time is lost due to the fact that the server sends and receives sequentially the buffers. It only has the advantage to have on the client size a pretty easy scheduler: Wait for buffer (MPI_Recv) -> Analyse it -> Send result (MPI_Send) My wish is to mix MPI_Send/MPI_Recv and other mpi functions like MPI_BCast/MPI_Scatter/MPI_Gather... (like I imagine every mpi application does). The problem is that I cannot find a easy solution in order that each client knows which kind of mpi function is currently called by the server. If the server calls MPI_BCast the client should do the same. Sending at each time a first message to indicate the function the server will call next does not look very nice. Though I do not see an easy/best way to implement an "adaptative" scheduler on the client side. Any tip, advice, help would be appreciate. Thanks, Olivier
