Test script for the realtime performance of Julia

RealTime.jl

using Winston

const SIMUL_DUR  = 10.0      # simulation time in seconds
const PeriodTime = 20e-3     # period time for the simulation in seconds
const workload = 20000       # workload in vector additions/ multiplications per simulation step
const vec_size = 3

const cpu_usage = zeros(round(Int, SIMUL_DUR / PeriodTime)) # data array to log the cpu usage
const vec = zeros(vec_size, workload) # preallocate data array of 3D vectors

function step(step)
    # sleep until the next simulation interval starts
    while abs(mod(time(), PeriodTime)) > 1e-3
        sleep(0.001)
    end    
    tic();
    for i in 1:workload # do some work
        vec[:,i] += ones(vec_size)
        vec[:,i] *= 2.2
    end    
    cpu_usage[step] = toq() / PeriodTime;
end

function main()
    step(1) # precompile the function step
    step(2) # start the garbage collector
    for i in 1:round(Int, SIMUL_DUR / PeriodTime)
        step(i)
        if mod(i, 100) == 0
            println("Steps: $i")
        end
    end    
    crest_factor = maximum(cpu_usage) / mean(cpu_usage)
    min_time = minimum(cpu_usage) * PeriodTime
    max_time = maximum(cpu_usage) * PeriodTime
    jitter = (max_time - min_time) * 1000
    println("Jitter [ms]: $jitter")
    println("Crest factor: $crest_factor")
    plot(cpu_usage)
end

To run this test script type:
include("RealTime.jl")
main()