Intel® Trace Analyzer and Collector User and Reference Guide
Buffer Given to MPI Cannot Be Read or Written
During the check for
of a send buffer Intel® Trace
Collector will read each byte in the buffer once. This works for contiguous as well
as non-contiguous data types. If any byte cannot be read because the memory is
is reported. This is an error because it
is only possible to proceed by skipping the entire operation.
check also disables the
accessibility check and send operations are then treated like receive operations:
for receive operations no similar check is performed because the MPI standard does
not say explicitly that the whole receive buffer has to be accessible - only the
part into which an incoming message actually gets copied must be writable.
Violations of that rule are caught and reported as fatal