This:

my @threads;
for(my $i = 0; $i < $numthreads; ++$i) {
    my $thread = threads->create(\&fetch,$i);
    push(@threads, $thread);
}
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..can be easily shorten to true perl'ish:

my @threads = map { threads->create \&fetch, $_ } 0 .. $numthreads-1;
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