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From: Oscar Benjamin <oscar.j.benjamin@gmail.com>
Date: Thu, 19 Sep 2013 15:48:53 +0100
Subject: Re: iterating over a file with two pointers
To: Peter Otten <__peter__@web.de>
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On 19 September 2013 15:38, Peter Otten <__peter__@web.de> wrote:
>> While running the above python.exe was using 6MB of memory (according
>> to Task Manager). I believe this is because tee() works as follows
>> (which I made up but it's how I imagine it).
>
> [...]
>
>> However, when I ran the above script on Python 2.7 it did consume
>> massive amounts of memory (1.6GB) and ran slower so maybe this depends
>> on optimisations that were introduced in 3.x.
>
> Did you use xrange()?

No I didn't. :)

Okay so it only uses 4.6MB of memory and it runs at the same speed:
there's no problem with chaining tee objects as long as you discard
them. If you don't discard them then a script like the one I wrote
would quickly blow all the system memory.


Oscar