Here's the situation - I'm using Event, and am using it's timeout feature (Event::Stats). However, the procedure that's beeing watched contains variable number of steps, logically this goes like this 
foreach $task (@tasks) {
 $task->do_one_task()
};

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Taks that could hang include 'do_one_task' and 'foreach'. Each step should finish in under 20 seconds, but because there are up to 100 of steps involved, I need to set unreasonably large timeout value, like 2000 seconds for the whole subroutine.

This is bad because every single step can go into infinite loop, I should be able to detect this in under 30 seconds, and because I'm using aggegate values I won't know about the job hanging until 2000 seconds later.

I would like to split one big timeout value for this whole code block, into few smaller ones, essentially this means that I would like to convert this code into something like this: 

foreach $task (@tasks) {
       $task->do_one_task();
        pong(); # Report back to Event::Stats that I'm
        # still alive and that it should reset it's timer
};

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Alternatively I would need to use something like coroutines, but I think this would be way beyond my skill, ie: 
 call_with_timeout(mysubroutine,$low_timeout);

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where mysubroutine would recall the place where it last finished, ie 
  $self->MagicallyRecallState(); # and jump to the correct
          #codeblock
 foreach $sth (@sth) {
    $self->SaveState() && return;
   $sth->method();
};

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Which approach is the best (and I'm not sure if this coroutine-like solution is at all possible with perl)?

update 

  for (0..int(rand(1000))) {
    sleep(int(rand(10)));# this takes at most 10s  
 };

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In reply to Splitting one large timeout into few smaller ones.. by Eyck

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