The benchmark reports per-element times for summing the elements of a typed-data List.
----
The VM implementation is quite good but it looks like there is still a little room for improvement since the views are 2x slower than a simple array.
dart compile exe:
TypedDataPoly.mono.array.2(RunTime): 1.9670880036279512 ns.
TypedDataPoly.A_V.array.2(RunTime): 4.392355 ns.
TypedDataPoly.A_V.view.2(RunTime): 5.730097499999999 ns.
TypedDataPoly.A_UV.array.2(RunTime): 4.455393750000001 ns.
TypedDataPoly.A_UV.view.2(RunTime): 5.811122500000001 ns.
TypedDataPoly.A_VUV.array.2(RunTime): 4.386336250000001 ns.
TypedDataPoly.A_VUV.view.2(RunTime): 5.7639675 ns.
TypedDataPoly.A_UVx5.array.2(RunTime): 4.62768 ns.
TypedDataPoly.A_UVx5.view.2(RunTime): 5.7099649999999995 ns.
TypedDataPoly.mega.array.2(RunTime): 5.272632499999999 ns.
TypedDataPoly.mega.mixed.2(RunTime): 5.62861 ns.
TypedDataPoly.mono.array.100(RunTime): 0.6455633088733822 ns.
TypedDataPoly.A_V.array.100(RunTime): 3.1558100965636964 ns.
TypedDataPoly.A_V.view.100(RunTime): 4.476973567105732 ns.
TypedDataPoly.A_UV.array.100(RunTime): 3.149724878714137 ns.
TypedDataPoly.A_UV.view.100(RunTime): 4.500062299750802 ns.
TypedDataPoly.A_VUV.array.100(RunTime): 3.1438380581862146 ns.
TypedDataPoly.A_VUV.view.100(RunTime): 4.499246259421757 ns.
TypedDataPoly.A_UVx5.array.100(RunTime): 3.1570175999999996 ns.
TypedDataPoly.A_UVx5.view.100(RunTime): 4.482889818440727 ns.
TypedDataPoly.mega.array.100(RunTime): 3.649420567570034 ns.
TypedDataPoly.mega.mixed.100(RunTime): 4.068594455581881 ns.
On the other hand, there is a massive performance tax for using UnmodifiableUint8ListView on the web, especially views of views.
https://github.com/dart-lang/sdk/issues/50255 discusses how this might be fixed.
compile js -O3:
TypedDataPoly.mono.array.2(RunTime): 2.209502118308509 ns.
TypedDataPoly.A_V.array.2(RunTime): 2.58625 ns.
TypedDataPoly.A_V.view.2(RunTime): 2.32 ns.
TypedDataPoly.A_UV.array.2(RunTime): 51.633530557495135 ns.
TypedDataPoly.A_UV.view.2(RunTime): 302.4986387561256 ns.
TypedDataPoly.A_VUV.array.2(RunTime): 52.19476512355694 ns.
TypedDataPoly.A_VUV.view.2(RunTime): 302.84394312113756 ns.
TypedDataPoly.A_UVx5.array.2(RunTime): 55.649763488505165 ns.
TypedDataPoly.A_UVx5.view.2(RunTime): 849.458699173131 ns.
TypedDataPoly.mega.array.2(RunTime): 59.75952192382461 ns.
TypedDataPoly.mega.mixed.2(RunTime): 142.7126082991336 ns.
TypedDataPoly.mono.array.100(RunTime): 0.9815000000000002 ns.
TypedDataPoly.A_V.array.100(RunTime): 1.1626947678735444 ns.
TypedDataPoly.A_V.view.100(RunTime): 1.2075 ns.
TypedDataPoly.A_UV.array.100(RunTime): 17.17602868362643 ns.
TypedDataPoly.A_UV.view.100(RunTime): 231.5 ns.
TypedDataPoly.A_VUV.array.100(RunTime): 16.85678073510773 ns.
TypedDataPoly.A_VUV.view.100(RunTime): 229.7 ns.
TypedDataPoly.A_UVx5.array.100(RunTime): 17.01657458563536 ns.
TypedDataPoly.A_UVx5.view.100(RunTime): 697.5524475524476 ns.
TypedDataPoly.mega.array.100(RunTime): 22.770700636942674 ns.
TypedDataPoly.mega.mixed.100(RunTime): 94.4 ns.
Change-Id: If8878efd4c57bbd87effcd1d3f1339bc0cffbd75
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/264897
Commit-Queue: Stephen Adams <sra@google.com>
Reviewed-by: Sigmund Cherem <sigmund@google.com>
