I don't use Thread::Queue myself, but I had this old sample around that says it's kindof obsolete, I may be wrong. Maybe try this style?

#!/usr/bin/perl
#leaks memory- Threads::Queue is for the old Threads <5.7
use strict;
use threads;
use Thread::Queue;
my @threads;
my $thread;

my $q = Thread::Queue->new();
$q->enqueue(1..100000);
print "Items in the queue: ",$q->pending,"\n";
for (1..5) {
   push @threads, threads->new(\&ttest);
   print "spawned thread:";
}
foreach $thread (@threads){
   $thread->join;
}

sub ttest {
   while (my $cnt =  $q->pending) {
       my $item = $q->dequeue;
       print "$cnt\n";
   last if $cnt == 0 ;
   }
}
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