Threads are not deprecated. Threads are fully supported.

The docs say that threads are discouraged. When pressed for an explanation, the reason given for that message was that ...threads are hard and the people in some IRC channel don't want to answer questions about threads?

Ok, that might not be exactly right, but the answer I got back was clear a mud. Read it for yourself.

What's relevant to me is this:

As one of several people who have maintained the various threads modules over the years, I regret that I missed being part of the original discussion that lead to the inclusion of the 'discouraged' message.

The fact is that threads work, they are maintained, and they currently do not have any bugs preventing their use. I acknowledge that not all Perl modules are thread-safe, but there is sufficient documentation to that affect in the POD.

There's also a performance penalty to adding thread support to a Perl, but that penalty applies to whether you use threads or not, and it's pretty common for the system perl to have thread support, so you're probably already suffering from that penalty.