[Developers] Re: behavior of HorizonRadiusInDirection

[Jonathan Thornburg]

Hi, Yosef,

I've just committed a change to AHFinderDirect which should fix your bug.
Basically, you need to set the (new) parameter
   AHFinderDirect::always_broadcast_horizon_shape = true
to make  HorizonRadiusInDirection()  work reliably on multiple processors.
Please let me know if this doesn't solve your problem.

Setting this parameter will make AHFinderDirect communicate a bit more
data between processors, so this isn't the default.  We could change this
(make the default be the "safe but slower" case) if people want.  Comments?

[Hmm, maybe some benchmarks are in order.  What's a machine we use
where a  CCTK_ReduceLocArrayToArray1D()  is particularly slow?]

ciao,

-- 
-- Jonathan Thornburg <jthorn at aei.mpg.de>
    Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut),
    Golm, Germany, "Old Europe"     http://www.aei.mpg.de/~jthorn/home.html
    "Washing one's hands of the conflict between the powerful and the
     powerless means to side with the powerful, not to be neutral."
                                       -- quote by Freire / poster by Oxfam