The topic of the "early completion" behavior in OB1 for IB
optimizations has come up several times in the v1.2 series (it causes
problems in some scenarios).
- leave the default the way it is now (early completions enabled)
- add an MCA parameter for disabling early completions
I mention this now because I had a customer complain about it over the
weekend. :-)
Gleb and I propose the patch in https://svn.open-mpi.org/trac/ompi/ticket/1224
for the v1.2 series. The new OB1 MCA parameter
pml_ob1_use_early_completions defaults to 1 (preserving the same
behavior as the rest of the v1.2 series), but it can be set to 0 if
the early completions on IB are creating problems for specific
applications.
It would be good to get this functionality in a real release (e.g.,
v1.2.6).
Note that this MCA parameter is not necessary for the upcoming v1.3
series because of changes in ob1 and the openib btl.
--
Jeff Squyres
Cisco Systems
