# [Mpi3-tools] MPI_T - Reviews and Question on Initialization

Martin Schulz schulzm at llnl.gov
Thu Jun 30 03:22:12 CDT 2011

Hi all,

First, just a quick reminder that we need to have the MPI_T
document in a final draft state by Monday to make the two
week deadline for the MPI forum. Hence, if you have any
comments that are more than ticket 0 changes, please let
me know. Also, if you edit the document directly, please
make sure to update your SVN repository, since people
are making changes to it (and send me email afterwards).

I am traveling Saturday-Tuesday. I would appreciate
any comments, especially larger changes, before the
weekend.

Further, Bronis has been going over the document and
making comments. One in particular I wanted to pass
along and put up for discussion. This is regarding the
MPI_T_Init_thread behavior, which we discussed before
on one of our TelCons. At that time, we decided to add
the following advice to users (p.39):

\begin{users}
The MPI specification does not require all MPI processes to exist
before the call to MPI_INIT.  If the MPI tool information interface is
used before MPI_INIT has been called, MPI_T_INIT_THREAD
must be called on each process that exists.  Processes created by
the MPI implementation during MPI_INIT inherit the status of MPI
tool information interface (whether it is initialized or not as well as
all active handles) from the process from which they are created.
\end{users}

Here is Bronis's comment:

The advice to users on page 39 is not just advice to users.
The problem is that I do not see anywhere that requires inheritance
of the tool information interface state. You only mention it in this
advice to users, which is non-normative. You need a normative statement
that it is inherited.

I know we wanted to be careful when we wrote that part, but
I kind of agree with Bronis, that this should be stronger. Would
it be OK to just drop the "advice" environment, i.e., make the
text that is now an advice to a regular part of the document?

Thanks!

Martin

________________________________________________________________________
Martin Schulz, schulzm at llnl.gov, http://people.llnl.gov/schulzm
CASC @ Lawrence Livermore National Laboratory, Livermore, USA