This is a commonly asked question, though I'm unsure whether it is listed in the FAQ:

How do I do expensive operation XXX on my 30 GB file?

The correct answer is: one line at a time.

--
TTTATCGGTCGTTATATAGATGTTTGCA

In reply to Re: Deleting internal array elements by TomDLux
in thread Deleting internal array elements by Itatsumaki

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