This is good stuff. However, having downloaded your CPAN module. Note that I changed the code above so it does a descending sort e.g.
for (rikeysort {/^\w+\s+(\d+)/; $2} <INPF>) {

[download]
This error now occurs 
Can't call method "rikeysort" on an undefined value at ./x.pl line 401
+, <INPF> line 12.

[download]
There are only 12 records in my test input file
It works fine if I use ascending key sort
Any ideas what is happenning here ?

In reply to Re^2: most efficient buffer sort by Anonymous Monk
in thread most efficient buffer sort by Anonymous Monk

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