Coalesced Buffer Communication #6050

Job	Run time
CI-Cuda-Host (g++, Release, cuda, serial)	42m 25s
CI-Rocm-HIP (hipcc, Release, hip, serial)	32m 50s
CI-Cuda-Host (g++, Release, cuda, mpi)	42m 21s
CI-Rocm-HIP (hipcc, Release, hip, mpi)	35m 9s
CI-Cuda-Host (g++, Release, host, serial)	12m 20s
CI-Rocm-HIP (hipcc, Debug, hip, serial)	54m 52s
CI-Cuda-Host (g++, Release, host, mpi)	12m 15s
CI-Rocm-HIP (hipcc, Debug, hip, mpi)	56m 49s
CI-Cuda-Host (g++, Debug, cuda, serial)	1h 18m 13s
CI-Cuda-Host (g++, Debug, cuda, mpi)	1h 16m 27s
CI-Cuda-Host (g++, Debug, host, serial)	10m 54s
CI-Cuda-Host (g++, Debug, host, mpi)	10m 47s
CI-Cuda-Host (clang++-15, Release, cuda, serial)	26m 58s
CI-Cuda-Host (clang++-15, Release, cuda, mpi)	27m 34s
CI-Cuda-Host (clang++-15, Release, host, serial)	9m 41s
CI-Cuda-Host (clang++-15, Release, host, mpi)	9m 55s
CI-Cuda-Host (clang++-15, Debug, host, serial)	8m 9s
CI-Cuda-Host (clang++-15, Debug, host, mpi)	7m 53s
	9h 15m 32s

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