In [1]:

versioninfo()

Julia Version 1.6.0-rc1
Commit a58bdd9010 (2021-02-06 15:49 UTC)
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: AMD Ryzen 5 3500 6-Core Processor              
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-11.0.1 (ORCJIT, znver2)

In [2]:

using Distributed

addprocs()
@show nprocs()
@show nworkers()

nprocs() = 7
nworkers() = 6

Out[2]:

In [3]:

@everywhere using Random

In [4]:

@everywhere function ntoone(rng=Random.default_rng())
    s = rand(rng)
    for n in Base.Iterators.countfrom(2)
        s += rand(rng)
        s < 1 || return n
    end
end

In [5]:

function estimate_e(N=10^6; rngfunc=Random.default_rng)
    S = @distributed (+) for _ in 1:N
        ntoone(rngfunc())
    end
    S / N
end

estimate_e(10)

Out[5]:

3.1

In [6]:

@time estimate_e(10^8)

  0.288376 seconds (572 allocations: 24.297 KiB)

Out[6]:

2.71821524

In [7]:

@time estimate_e(10^9)

  2.866110 seconds (630 allocations: 25.516 KiB)

Out[7]:

2.718281449

In [8]:

@time estimate_e(10^10)

 28.454274 seconds (1.29 k allocations: 47.047 KiB)

Out[8]:

2.7182888143