[Mpi3-rma] Updated Proposal 1
dinan at mcs.anl.gov
Sun Nov 28 10:40:41 CST 2010
On 11/26/10 4:37 PM, Jeff Hammond wrote:
> What is the use case multi-element RMW anyways? I'm definitely going
> to need message-atomic put, but I'll do the portable i.e. MPI version
> with RMW-lock + put + RMW-unlock.
For dynamic windows, a portable pointer will be something like <process,
displacement>. If you want to build lock-free data structures, you'd
want to do swap on pointers. If you can't do both atomically, then you
will need to do things differently anyway. Providing a count for this
function could be misleading, I'd suggest some text to clarify.
Jeff, unless you need trylock there are more efficient ways to do
one-sided locking on top of existing MPI-2 RMA that don't require
polling over the network. I can point you to code if you're interested,
I think it's in an MPICH example somewhere.
More information about the mpiwg-rma