Reduce redundant GPU allocations #1327

	name: Benchmarks

	on:
	pull_request:
	branches: [ master ]
	paths-ignore: 'doc/**'

	jobs:
	build:
	name: "Benchmarks"
	runs-on: ubuntu-22.04
	strategy:
	fail-fast: false
	env:
	CC: gcc-12
	CXX: g++-12
	steps:
	- name: Get build dependencies
	run: \|
	sudo apt-get update
	sudo apt-get install -y ninja-build ccache
	- name: Set up cmake
	uses: jwlawson/[email protected]
	with:
	cmake-version: 3.22.x
	- name: Clone w/ submodules
	uses: actions/checkout@v4
	with:
	submodules: recursive
	# figure out vector extensions for ccache key
	- name: Check vector extensions
	run: \|
	HAS_AVX512F=$([[ $(lscpu \| grep "avx512f" \| wc -l) -eq 1 ]] && echo "_avx512f" \|\| echo "")
	HAS_AVX2=$([[ $(lscpu \| grep "avx2" \| wc -l) -eq 1 ]] && echo "_avx2" \|\| echo "")
	HAS_FMA=$([[ $(lscpu \| grep "fma" \| wc -l) -eq 1 ]] && echo "_fma" \|\| echo "")
	HAS_AVX=$([[ $(lscpu \| grep "avx" \| wc -l) -eq 1 ]] && echo "_avx" \|\| echo "")
	VECTOR_EXTENSIONS=${HAS_AVX512F}${HAS_AVX2}${HAS_FMA}${HAS_AVX}
	echo "VECTOR_EXTENSIONS=$VECTOR_EXTENSIONS" >> $GITHUB_ENV
	- name: Setup ccache
	uses: hendrikmuhs/[email protected]
	with:
	key: benchmarks-${{ env.CXX }}-${{ env.VECTOR_EXTENSIONS }}
	- name: Build arbor
	run: \|
	mkdir build
	cd build
	cmake .. -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_COMPILER=$CXX -DCMAKE_C_COMPILER=$CC -DARB_WITH_MPI=OFF
	ninja -j4 ubenches
	cd -
	- name: Run benchmarks
	run: \|
	build/bin/accumulate_functor_values
	build/bin/default_construct
	build/bin/event_setup
	build/bin/event_binning
	build/bin/fvm_discretize
	build/bin/mech_vec
	build/bin/task_system

Provide feedback