>> Permission to ask potentially dumb questions?
>
> Not dumb at all.
Thanks. I was scared that Barry would tell me I should quit my job
(again) if I asked a dumb question :-)
And the high-level goal that brought me here was to understand PETSc's
use of MPI-3 features, including RMA. If there's
Jeff Hammond writes:
> Permission to ask potentially dumb questions?
Not dumb at all.
> 1) Implementing atomic read-modify-write using
> Lock->Get->Accumulate->Unlock is W.R.O.N.G. Get and Accumulate are
> NOT guaranteed to be ordered within any epoch. Ever. You appear to
> be leveraged the
Permission to ask potentially dumb questions?
In this code (src/vec/is/sf/impls/window/sfwindow.c in git master as
of 7fb8eca36577947f0d4ded035522334534bc7e38):
static PetscErrorCode PetscSFFetchAndOpBegin_Window(PetscSF
sf,MPI_Datatype unit,void *rootdata,const void *leafdata,void
*leafupdate,MP
