salva's suggestion of using the system  sort followed by duplicate line consolidation seems the ideal way to go. It's a multi-key sort, but the keys don't seem wonky to the point  sort would choke on them; even if they were, an intermediate processing step to produce a 'normalized' file to feed to  sort would, while a bit tedious, be fairly straight-forward, quick and highly scalable. Am I missing something?

In reply to Re^2: perl ST sort performance issue for large file? by AnomalousMonk
in thread perl ST sort performance issue for large file? by rkshyam

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