Coalesced Buffer Communication #6038

Job	Run time
CI-Cuda-Host (g++, Release, cuda, serial)	42m 40s
CI-Cuda-Host (g++, Release, cuda, mpi)	41m 37s
CI-Rocm-HIP (hipcc, Release, hip, serial)	33m 34s
CI-Cuda-Host (g++, Release, host, serial)	11m 42s
CI-Rocm-HIP (hipcc, Release, hip, mpi)	33m 30s
CI-Cuda-Host (g++, Release, host, mpi)	12m 4s
CI-Rocm-HIP (hipcc, Debug, hip, serial)	55m 0s
CI-Cuda-Host (g++, Debug, cuda, serial)	1h 13m 11s
CI-Rocm-HIP (hipcc, Debug, hip, mpi)	55m 20s
CI-Cuda-Host (g++, Debug, cuda, mpi)	1h 14m 27s
CI-Cuda-Host (g++, Debug, host, serial)	10m 57s
CI-Cuda-Host (g++, Debug, host, mpi)	11m 4s
CI-Cuda-Host (clang++-15, Release, cuda, serial)	27m 44s
CI-Cuda-Host (clang++-15, Release, cuda, mpi)	28m 19s
CI-Cuda-Host (clang++-15, Release, host, serial)	9m 50s
CI-Cuda-Host (clang++-15, Release, host, mpi)	10m 1s
CI-Cuda-Host (clang++-15, Debug, host, serial)	7m 35s
CI-Cuda-Host (clang++-15, Debug, host, mpi)	7m 45s
	9h 6m 20s

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