[mpiwg-rma] same_op_no_op

[Jed Brown]

Jeff Hammond <jeff.science at gmail.com> writes:

> There's an easy solution for "bad" ops: fall back to C&S
> implementation the way one does on any shared memory arch when a
> particular atomic isn't supported but C&S is.
>
> This means that no mutexes are required, NICs that have HW support for
> NO_OP, REPLACE, SUM, XOR, etc. can use them, and when a user asks for
> something silly like PROD, the performance is degraded for those ops
> alone and not for anything else.

1. How does the above not justify the same for M**LOC?

2. Now we expect every system to have the equivalent of CMPXCHG16B and
that basic types will never be longer than 16B (unless a longer atomic
is made available)?
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 835 bytes
Desc: not available
URL: <http://lists.mpi-forum.org/pipermail/mpiwg-rma/attachments/20140314/98b0bb84/attachment-0001.pgp>