In essence, all you need is:

use threads::shared;

my @map :shared;
...
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But then, you need to use locking to prevent corruption through concurrent updates. And you'll also need to ensure that your objects are compatible with threading.

All of this is documented in the module you mentioned: threads::shared. So rather than expecting us to reiterate all the information that you already have at your finger tips, you'd be more likely to get a response if you told us what you don;t understand; or better yet, what you've had trouble with implementing.

As it is, you don't appear to have made any attempt to use the module you've pointed out you need.