function sumN(N)
s = zero(N)
for i in 1:N
s += i
end
s
end
julia> @btime sumN(N) setup=(N=1_000_000)
2.424 ns (0 allocations: 0 bytes)
500000500000
julia> @btime sumN(N) setup=(N=1_000_000e0)
2.424 ns (0 allocations: 0 bytes)
500000500000
julia> @btime sumN(N) setup=(N=1_000_001e0)
1.330 ms (0 allocations: 0 bytes)
5.00001500001e11
julia> @btime sumN(N) setup=(N=1_000_001)
1.330 ms (0 allocations: 0 bytes)
5.00001500001e11
julia> @btime sumN(M) setup=(M=1_000_001)
1.993 ns (0 allocations: 0 bytes)
500001500001The Float64 trial should run slowly, and return a Float64, whereas the Int trial should run in a couple of ns and return an Int. Is there some caching of the setup going on, which uses == instead of ===?
The
Float64trial should run slowly, and return aFloat64, whereas theInttrial should run in a couple of ns and return anInt. Is there some caching of thesetupgoing on, which uses==instead of===?