MPI_Accumulate with MPI_REPLACE accomplishes a put. NO_OP is not permitted in MPI_Accumulate. On 9/7/12 5:23 PM, Torsten Hoefler wrote:

All,

So it may be fine for some accumulate ops but not for all because MPI_Accumulate with MPI_NO_OP was our back-door to get an atomic put. Thanks to Keith for pointing this out!

Thanks, Torsten

On Fri, Sep 07, 2012 at 04:40:54PM -0500, Torsten Hoefler wrote:

...

Hi Jim,

I agree, that is a reasonable change.

Best, Torsten

On Thu, Sep 06, 2012 at 10:48:47AM -0500, James Dinan wrote:

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Hi All,

It looks like we forgot to specify that for MPI_NO_OP in the new accumulate ops, the origin buffer is ignored (i.e. it's acceptable to pass NULL). We can add this text on page 441, line 30:

When MPI_NO_OP is specified, the origin buffer is ignored.

We already have such a use case in the linked list example.

~Jim. _______________________________________________ mpi3-rma mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma

-- ### qreharg rug ebs fv crryF ------------- http://www.unixer.de/ ----- Torsten Hoefler | Assistant Professor Dept. of Computer Science | ETH Z�rich Universit�tsstrasse 6 | Zurich-8092, Switzerland CAB E 64.1 | Phone: +41 76 309 79 29 _______________________________________________ mpi3-rma mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma