[petsc-users] DMDA halo exchange

[Dominic Meiser]

Hi,

I have a DMDA for a structured grid in a 3D FDTD calculation. What is 
the most efficient way to update the ghost regions after each time step? 
Currently I update a global vector and then I scatter to a local vector 
using DMGlobalToLocalBegin/End for the next time step. I also tried 
DMLocalToLocal with the same source and target vector and that appears 
to be slightly faster, perhaps due to better cache usage in the copy of 
the owned region. Ideally I would like to update just the ghost cells 
from the owned regions. Is there a good way to do that? Something 
similar to VecGhostUpdateBegin/End?

Thanks,
Dominic

-- 
Dominic Meiser
Tech-X Corporation
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Boulder, CO 80303
USA
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