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To: python-list@python.org
From: Dave Angel <davea@davea.name>
Subject: Re: Processing large CSV files - how to maximise throughput?
Date: Fri, 25 Oct 2013 03:57:17 +0000 (UTC)
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On 24/10/2013 23:35, Steven D'Aprano wrote:

> On Fri, 25 Oct 2013 02:10:07 +0000, Dave Angel wrote:
>
>>> If I have multiple large CSV files to deal with, and I'm on a
>>> multi-core machine, is there anything else I can do to boost
>>> throughput?
>> 
>> Start multiple processes.  For what you're doing, there's probably no
>> point in multithreading.
>
> Since the bottleneck will probably be I/O, reading and writing data from 
> files, I expect threading actually may help.
>
>
>

We approach the tradeoff from opposite sides.  I would use
multiprocessing to utilize multiple cores unless the communication costs
(between the processes) would get too high.

They won't in this case.

But I would concur -- probably they'll both give about the same speedup.
I just detest the pain that multithreading can bring, and tend to avoid
it if at all possible.

-- 
DaveA