Perl has a clever internal strategy to make arrays as flexible and fast as possible, to allow immediate push and unshift of data, with rare need of allocating or moving.

This comes with the cost of extra allocated space.

If one doesn't need this flexibility and data elements are of fixed size, it's not uncommon to use a byte° string as workaround and to address and replace elements with substr , in order to safe space.

°) I e not utf8