[ANN] ArrayAllocators.jl v0.3 composes with OffsetArrays.jl v1.12.1+ for faster zeros with offset indexing

Package Announcements
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Another feature of ArrayAllocators.jl v0.3 is an alternate implementation of zeros via calloc. Note that this ArrayAllocators.zeros is not exported. Here ArrayAllocators.zeros(T, ...) is essentially just Array{T}(calloc, ...).

julia> using ArrayAllocators

julia> @time AAZ = ArrayAllocators.zeros(Int, 1024, 1024, 1024);
  0.029364 seconds (61.31 k allocations: 8.004 GiB, 99.89% compilation time)

julia> @time AAZ = ArrayAllocators.zeros(Int, 1024, 1024, 1024);
  0.000037 seconds (4 allocations: 8.000 GiB)

julia> @time BZ = Base.zeros(Int, 1024, 1024, 1024);
  4.448959 seconds (2 allocations: 8.000 GiB, 0.52% gc time)

julia> @time BZ = Base.zeros(Int, 1024, 1024, 1024);
  4.665584 seconds (2 allocations: 8.000 GiB, 2.48% gc time)

Note that on some operating systems this may defer the actual allocation of memory until writing.

julia> @time fill!(AAZ, 1)
  4.849603 seconds (8.17 k allocations: 491.429 KiB, 0.64% compilation time)

julia> @time fill!(AAZ, 2);
  1.634943 seconds

julia> @time fill!(BZ, 1);
  1.710879 seconds

julia> @time fill!(BZ, 2);
  1.717882 seconds

If you wanted to switch your code to use ArrayAllocators.zeros instead of Base.zeros, you can import it before your first reference to zeros.

julia> using ArrayAllocators: zeros

julia> @time zeros(Int, 1024, 1024, 1024);
  0.000028 seconds (4 allocations: 8.000 GiB)

julia> @time Base.zeros(Int, 1024, 1024, 1024);
  4.442414 seconds (2 allocations: 8.000 GiB, 0.10% gc time)

While this may look like a free lunch, note @Sukera’s caveats in the original post:

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