Scyld and MPICH.

William Gropp gropp at
Thu Nov 6 12:48:24 EST 2003

At 10:55 AM 11/6/2003, Zukaitis, Anthony wrote:
>I am having a problem with MPI_reduce and I believe that it is a buffer size
>error.  Is there a way to calculate the maximum size of the buffer and what
>is the maximum size of the buffer allowed?  It does not seem to be linear
>with the number of processors.

There should be no maximum buffer size, though the ch_p4 device does impose 
a limit when shared memory is used to transfer a message.  Do you have an 
example program that we could test (Bug reports for MPICH should be sent to 
mpi-maint at


Beowulf mailing list, Beowulf at
To change your subscription (digest mode or unsubscribe) visit

More information about the Beowulf mailing list