Optimize Indexable#each_slice(&)
#14864
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+67
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If the elements of an
Enumerable
are already stored contiguously in memory and each iteration returns a freshArray
(i.e.reuse
isfalse
or unset), it is faster to construct that returned array's contents with a single slice copy than inserting repeatedly. Benchmarks:Results: (raw output)
Same graph with time divided by
n
: (the bottom ones have a greaterm
)These results were taken on an x86-64 machine, where the
Slice
implementation starts to outmatch theIndexable
one whenm
is around 5 to 8. On AArch64 this number is slightly higher, so for simplicity the heuristic usesSMALL_SLICE_SIZE = 16
.