Another recent topic here led me to this article: www.sysarch.com/Perl/sort_paper.html. It shows that of two seemingly identical sorts: 

@fast = sort @unsorted;
@slow = sort { $a <=> $b } @unsorted;

[download]

The first one is faster because it runs entirely in C in the Perl core, while the second is slower because the sortsub executes in Perl code.

I was sorting tens of thousands of files by creation time in reverse chronological order, and was delighted to find the first one below faster than the second: 

@fast = reverse sort @unsorted;
@slow = sort { $b <=> $a } @unsorted;

[download]

kyle, I wonder how your median_sort might benchmark if it used my @s = sort @_;?

In reply to Re: A heap of medians: efficiency vs. speed by hbm
in thread A heap of medians: efficiency vs. speed by kyle

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