Strong scaling performance, Sphere benchmark, K80, 64M particles
Performance in millions of particle-timesteps / second / node

Nodes	Kokkos/Cuda-1 (mpi)	Kokkos/Cuda-2 (mpi)
1	159.4 (2)	334.6 (4)
2	161 (2)	317.3 (4)
4	128.2 (2)	273.3 (4)
8	None	231.1 (4)

Run commands and logfile links for column Kokkos/Cuda-1

1	mpirun -np 4 --npersocket 1 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 2 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=2.mpi=2.gpu=2
2	mpirun -np 8 --npersocket 1 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 2 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=4.mpi=2.gpu=2
4	mpirun -np 16 --npersocket 1 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 2 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=8.mpi=2.gpu=2
8	None

Run commands and logfile links for column Kokkos/Cuda-2

1	mpirun -np 4 --npersocket 2 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 4 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=1.mpi=4.gpu=4
2	mpirun -np 8 --npersocket 2 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 4 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=2.mpi=4.gpu=4
4	mpirun -np 16 --npersocket 2 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 4 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=4.mpi=4.gpu=4
8	mpirun -np 32 --npersocket 2 --bind-to core spa_ride80_kokkos_cuda -sf kk -k on g 4 -pk kokkos reduction atomic comm threaded -v x 256 -v y 160 -v z 160 -v t 100 -in in.sphere.gpu.steps -log log.sparta.date=23Dec17.model=sphere.machine=ride80.pkg=kokkos_cuda.kind=strong.size=64M.node=8.mpi=4.gpu=4