Suppose I am creating multiple threads to download urls with LWP. Is there any difference between using LWP before the worker threads are created versus requiring LWP in each worker thread, i.e.: 
use LWP;
use threads;

sub worker_thread { ... }

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versus 
use threads;

sub worker_thread {
  require LWP;
  ...
}

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If the OS is important, I am mainly interested in what will happen under Linux.

It seems that the first approach could be more efficient if the threads are created with copy-on-write. On the other hand, I've also seen comments like this: 

    require LWP::Simple; ## Requiring prevent CLONE leaks.

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for instance in 759033. Is this a concern under Linux?

In reply to common modules and threads? by perl5ever

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