Struct of Arrays (SoA) vs Array of Structs (AoS)

General Usage Performance
18

I’ve been playing with the example @e3c6 proposed but instead of computing the total norm I computed the individual norm:

function normSoA(x)
  out = Array{Float64,1}(undef, length(x.real))
  for i in 1:length(x.real)
    @inbounds out[i] = sqrt(x.real[i]^2 + x.imag[i]^2)
  end
  out
end

function normAoS(x)
  out = Array{Float64,1}(undef, length(x))
  for i in 1:length(x)
    @inbounds out[i] = sqrt(x[i].real^2 + x[i].imag^2)
  end
  out
end

In that case benchmarking give the exact same results for both cases. Using code_llvm shows that both codes use <4 x double> SIMD instructions.

Not sure how to interpret those findings but I wanted to share it with you. I’m a new Julia user. :slight_smile:

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