Hash entries are returned in an apparently random order.  The actual random
order is specific to a given hash; the exact same series of operations
on two hashes may result in a different order for each hash. Any insertion
into the hash may change the order, as will any deletion, with the exception
that the most recent key returned by C<each> or C<keys> may be deleted
without changing the order. So long as a given hash is unmodified you may
rely on C<keys>, C<values> and C<each> to repeatedly return the same order
as each other. See L<perlsec/"Algorithmic Complexity Attacks"> for
details on why hash order is randomized. Aside from the guarantees
provided here the exact details of Perl's hash algorithm and the hash
traversal order are subject to change in any release of Perl.