Hi > mpi_irecv(workerNodeID, messageTag, bufferVector[row][column]) OpenMPI contains no function of this form. There is MPI_Irecv, but it takes a different number of arguments.
Or is this a boost method? If yes, i guess you have to make sure that the bufferVector[row][column] is large enough... Perhaps there is a boost forum you can check out if the problem persists Jody On Sun, Jul 11, 2010 at 10:13 AM, Jack Bryan <dtustud...@hotmail.com> wrote: > thanks for your reply. > The message size is 72 bytes. > The master sends out the message package to each 51 nodes. > Then, after doing their local work, the worker node send back the same-size > message to the master. > Master use vector.push_back(new messageType) to receive each message from > workers. > Master use the > mpi_irecv(workerNodeID, messageTag, bufferVector[row][column]) > to receive the worker message. > the row is the rankID of each worker, the column is index for message from > worker. > Each worker may send multiple messages to master. > when the worker node size is large, i got MPI_ERR_TRUNCATE error. > Any help is appreciated. > JACK > July 10 2010 > > ________________________________ > Date: Sat, 10 Jul 2010 23:12:49 -0700 > From: eugene....@oracle.com > To: us...@open-mpi.org > Subject: Re: [OMPI users] OpenMPI how large its buffer size ? > > Jack Bryan wrote: > > The master node can receive message ( the same size) from 50 worker nodes. > But, it cannot receive message from 51 nodes. It caused "truncate error". > > How big was the buffer that the program specified in the receive call? How > big was the message that was sent? > > MPI_ERR_TRUNCATE means that you posted a receive with an application buffer > that turned out to be too small to hold the message that was received. It's > a user application error that has nothing to do with MPI's internal > buffers. MPI's internal buffers don't need to be big enough to hold that > message. MPI could require the sender and receiver to coordinate so that > only part of the message is moved at a time. > > I used the same buffer to get the message in 50 node case. > About ""rendezvous" protocol", what is the meaning of "the sender sends a > short portion "? > What is the "short portion", is it a small mart of the message of the sender > ? > > It's at least the message header (communicator, tag, etc.) so that the > receiver can figure out if this is the expected message or not. In > practice, there is probably also some data in there as well. The amount of > that portion depends on the MPI implementation and, in practice, the > interconnect the message traveled over, MPI-implementation-dependent > environment variables set by the user, etc. E.g., with OMPI over shared > memory by default it's about 4Kbytes (if I remember correctly). > > This "rendezvous" protocol" can work automatically in background without > programmer > indicates in his program ? > > Right. MPI actually allows you to force such synchronization with > MPI_Ssend, but typically MPI implementations use it automatically for > "plain" long sends as well even if the user didn't not use MPI_Ssend. > > The "acknowledgement " can be generated by the receiver only when the > corresponding mpi_irecv is posted by the receiver ? > > Right. > > ________________________________ > The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with > Hotmail. Get busy. > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users >
