How to GC a SharedArray

General Usage
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6

Hi,
I think I am facing a similar issue. Here is another MWE:

using Distributed, SharedArrays

function parallel_compute()
    shared_array = SharedArray{Float64,1}(100_000)
    @sync @distributed for i in 1:100_000
        shared_array[i] = randn()
    end
    return sum(shared_array)
end

addprocs(4)

for t = 1:10
    x = parallel_compute()
    println(Sys.free_memory()/2^20)
end

rmprocs(workers())

when I run this code, the amount of free RAM available (printed in MiB in the main loop) keeps decreasing:

493.28515625
492.31640625
491.46875
478.390625
477.6640625
476.81640625
463.73828125
463.01171875
462.52734375
461.55859375

If I push it further (with more iterations and a more complex parallel_compute function), my code breaks because of memory shortage. I would also expect that the GC would help getting some free space after parallel_compute is called but it seems that it doesn’t. I tried sharred_array = nothing; GC.gc() at the end of parallel_compute but it didn’t help. Is this the expected behavior ? Am I missing something ?