You simply aren't going to beat the highly optimised C code using Perl.
Out of curiosity, I have been looking at the supposedly "highly optimised C code" of GNU sort and the reality is that it is not so highly optimised, it just uses a very naïve merge sort. In comparison, perl internal sortsv function is much more advanced...

In reply to Re^2: sorting very large text files by salva
in thread sorting very large text files by rnaeye

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