I'll take a shot at this. I believe the only variables which are shared between threads are those which are explicitly shared using the share declaration from use threads::shared. From the threads::shared documentation: 
By default, variables are private to each thread, and each newly cre-
ated thread gets a private copy of each existing variable.  This module
allows you to share variables across different threads (and pseudoforks
on Win32).  It is used together with the threads module.

In reply to Re: Is a called package in thread storage? by pc88mxer
in thread Is a called package in thread storage? by Wiggins

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