I'm tring to benchmark the Thread::Queue methods with the following simple code: 
use strict;
use Thread::Queue;
use Benchmark;

# this part works fine
my $queue = Thread::Queue->new();
timethis(1000, sub{$queue->enqueue(1);});
timethis(1000, sub{$queue->dequeue();});

# this part gets stuck.
# but works fine if I change dequeue() to dequeue_nb()
my $queue2 = Thread::Queue->new();
timethese(1000, {'Push'=>sub{$queue2->enqueue(1);},
        'Pop'=>sub{$queue2->dequeue();}
             }
          );

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It seems timethese() somehow get stuck on the dequeue() call, which is blocking if the queue is empty. It works fine if dequeue() is replaced by dequeue_nb(). But why does it get stuck? I thought timethese() does the testing in sequence, not in parallel, so the second test should be the same as the first two timethis(), what's wrong?

In reply to Benchmark does timethese() in parallell? by johnnywang

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