rand(1:10) vs Int(round(10*rand())

General Usage Performance
10

The algorithm here: https://arxiv.org/abs/1805.10941
is faster and is claimed to be unbiased.

EDIT: (Skip this. Corrected and improved code is in my following post)

mytrunc(x) = UInt64((x << 64) >> 64)
function nearlydivisionless(s)
    x = rand(UInt64)
    m = convert(UInt128, x) * s
    l = mytrunc(m)
    if (l < s)
        t = -s % s
        while l < t
            x = rand(UInt64)
            m = convert(UInt128, x) * s
            l = mytrunc(m)
        end
    end
    return Int(m >> 64)
end

function biased(s)
    return floor(Int, rand() * s)
end

Benchmarks:

julia> @btime nearlydivisionless(10);
  7.042 ns (0 allocations: 0 bytes)

julia> @btime biased(10);
  5.188 ns (0 allocations: 0 bytes)

julia> @btime rand(0:9);
  12.698 ns (0 allocations: 0 bytes)
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