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Functionality Adoption! and put it down! and channels in Julia

I am trying to run something similar to this:

y = @parallel (min) for i in collection
    f(i)
end

where f(i)is a function that basically is a loop whilethat counts how many iterations are required to fulfill its conditions. At the beginning of one of the termination conditions is a predetermined number of iterations n. However, if f(i)it ever returns less than n, then ideally I would like to replace it with na value f(i)(for example, since I am looking for a minimum f(i), if I have f(j), mI would like all other loops to stop checking if they have reached the tags m).

I am new to parallel computing, so I probably misinterpret the documentation , but I think I should do something like this:

x = Channel{Int64}(1)
put!(x,n)

y = @parallel (min) for i in collection
    f(i,x)
end

close(x)

where I changed fto take the parameter Channel, and now it looks something like this:

@everywhere function f(item,chan)
    going = true
    count = 0
    while (going)
        going = false
        # perform some operations
        if (count < fetch(chan) && !conditions_met())
            # conditions_met checks the other termination conditions
            going = true
            count += 1
        end
    end

    count += 1

    if (count < fetch(chan))
        take!(chan)
        put!(chan,count)
    end

    return count
end

If I replaced the first count < fetch(chan)with count < nand deleted another ifblock / code Channel, the script works fine. But since it nwill be several orders of magnitude more than the minimum f(i), if I could do something like what I described, this will greatly speed up the calculation. Is that what I would have to do, and if so, did I fit right?

Now I am experiencing the following error (works with 4 procs):

ERROR (unhandled task failure): On worker 3:
cannot resize array with shared data
 in shift! at array.jl:501
 in take! at channels.jl:54
 in f at /home/michael/Documents/julia/script.jl:98
 [inlined code] from /home/michael/Documents/julia/script.jl:126
 in anonymous at no file:0
 in anonymous at multi.jl:913
 in run_work_thunk at multi.jl:651
 [inlined code] from multi.jl:913
 in anonymous at task.jl:63
 in remotecall_fetch at multi.jl:737
 in remotecall_fetch at multi.jl:740
 in anonymous at multi.jl:1519
ERROR: LoadError: On worker 2:
cannot resize array with shared data
 in shift! at array.jl:501
 in take! at channels.jl:54
 in f at /home/michael/Documents/julia/script.jl:98
 [inlined code] from /home/michael/Documents/julia/script.jl:126
 in anonymous at no file:0
 in anonymous at multi.jl:913
 in run_work_thunk at multi.jl:651
 [inlined code] from multi.jl:913
 in anonymous at task.jl:63
 in preduce at multi.jl:1523
 [inlined code] from multi.jl:1532
 in anonymous at expr.jl:113
 [inlined code] from /home/michael/Documents/julia/script.jl:125
 in anonymous at no file:0
while loading /home/michael/Documents/julia/script.jl, in expression starting on line 121
ERROR (unhandled task failure): On worker 4:
cannot resize array with shared data
 in shift! at array.jl:501
 in take! at channels.jl:54
 in f at /home/michael/Documents/julia/script.jl:98
 [inlined code] from /home/michael/Documents/julia/script.jl:126
 in anonymous at no file:0
 in anonymous at multi.jl:913
 in run_work_thunk at multi.jl:651
 [inlined code] from multi.jl:913
 in anonymous at task.jl:63
 in remotecall_fetch at multi.jl:737
 in remotecall_fetch at multi.jl:740
 in anonymous at multi.jl:1519
ERROR (unhandled task failure): On worker 5:
cannot resize array with shared data
 in shift! at array.jl:501
 in take! at channels.jl:54
 in f at /home/michael/Documents/julia/script.jl:98
 [inlined code] from /home/michael/Documents/julia/script.jl:126
 in anonymous at no file:0
 in anonymous at multi.jl:913
 in run_work_thunk at multi.jl:651
 [inlined code] from multi.jl:913
 in anonymous at task.jl:63
 in remotecall_fetch at multi.jl:737
 in remotecall_fetch at multi.jl:740
 in anonymous at multi.jl:1519

98 - take!(chan) , 126 - f(i,x) for.

+4

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