Hi Massimo Just to make sure: usually the MPI_ERR_TUNCATE error is caused by buffer sizes that are too small. Can you verify that the buffers you are using are large enough to hold the data they should receive?
Jody On Sat, Feb 5, 2011 at 6:37 PM, Massimo Cafaro <massimo.caf...@unisalento.it> wrote: > Dear all, > > in one of my C codes developed using Open MPI v1.4.3 I need to call > MPI_Allreduce() passing as sendbuf and recvbuf arguments two MPI_PACKED > arrays. The reduction requires my own MPI_User_function that needs to > MPI_Unpack() its first and second argument, process them and finally > MPI_Pack() the result in the second argument. > > I need to use MPI_Pack/MPI_Unpack because I am not able to create a derived > datatype, since many data I need to send are dynamically allocated. > However, the code fails at runtime with the following message: > > An error occurred in MPI_Unpack > on communicator MPI_COMM_WORLD > MPI_ERR_TRUNCATE: message truncated > MPI_ERRORS_ARE_FATAL (your MPI job will now abort) > > I have verified that, after unpacking the data in my own reduction function, > all of the data are wrong. > Is this possible in MPI? I did not find anything on the "MPI reference Volume > 1" and "Using MPI" that prevents this. This should just require using as > datatype MPI_PACKED in MPI_Allreduce() . However, searching on the web I did > not find any examples. > > Thank you in advance for any clue/suggestions/source code examples. > This is driving me crazy now ;-( > > Massimo Cafaro > > > - > > ******************************************************************************************************* > > Massimo Cafaro, Ph.D. Additional affiliations: > Assistant Professor Euro-Mediterranean > Centre for Climate Change > Dept. of Engineering for Innovation SPACI Consortium > University of Salento, Lecce, Italy E-mail > massimo.caf...@unisalento.it > Via per Monteroni > massimo.caf...@cmcc.it > 73100 Lecce, Italy > caf...@ieee.org > Voice/Fax +39 0832 297371 > caf...@acm.org > Web http://sara.unisalento.it/~cafaro > > > ******************************************************************************************************* > > > > > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users >
