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Date: Sat, 20 Oct 2012 13:15:10 +1100
Subject: Re: Python does not take up available physical memory
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:31790

On Sat, Oct 20, 2012 at 9:22 AM, Pradipto Banerjee
<pradipto.banerjee@adainvestments.com> wrote:
> Dennis,
>
> 1. Yes, .readlines() work where .read() fails. Thanks for the suggestion - this has really given a big boost to the size of the data I can read.

If at all possible, consider reading the file iteratively and
retaining only the current line. You say you need to "compare one line
versus another" - are you able, for instance, to sort the file
(externally; I think every OS these days will have a sort utility that
can handle files >RAM) and then compare the current line against a
small amount of retained state? This sort (pun intended) of trick can
not only get you past the limit, it will often improve running time
enormously too.

ChrisA