Certainly for Perl 5, the cost of reference counting to performance is insignificant.

Twelve years after the initial release of Perl 5, there are still reference counting bugs -- and I don't just mean the circular reference problem.

In reply to Re^6: Parrot, threads & fears for the future. (ref counting) by chromatic
in thread Parrot, threads & fears for the future. by BrowserUk

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