# L-11 MCS 572 Fri 20 Sep 2024 : workcrew.jl

"""
Processing a job queue by many threads.
julia -t 4 workcrew.jl
to run with four threads.
"""

using Base.Threads

nbr = 10
jobs = rand((2, 3, 4, 5, 6), nbr)
println("The jobs : ", jobs)

nt = nthreads()
println("the number of threads : ", nt)

# start nt threads with the @threads macro
jobidx = Atomic{Int}(1)
@threads for i=1:nt
    println("Worker ", threadid(), " is ready.")
    while true
        myjob = atomic_add!(jobidx, 1)
        if myjob > nbr
            break
        end
        println("Worker ", threadid(),
		" spends ", jobs[myjob], " seconds",
		" on job ", myjob, " ...")
        sleep(jobs[myjob])
        jobs[myjob] = threadid()
    end
end
println("Jobs done : ", jobs)