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Re: Processing large CSV files - how to maximise throughput?

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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

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Thread

Processing large CSV files - how to maximise throughput? Victor Hooi <victorhooi@gmail.com> - 2013-10-24 18:38 -0700
  Re: Processing large CSV files - how to maximise throughput? Dave Angel <davea@davea.name> - 2013-10-25 02:10 +0000
    Re: Processing large CSV files - how to maximise throughput? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-25 03:35 +0000
      Re: Processing large CSV files - how to maximise throughput? Dave Angel <davea@davea.name> - 2013-10-25 03:57 +0000
      Re: Processing large CSV files - how to maximise throughput? Chris Angelico <rosuav@gmail.com> - 2013-10-25 17:13 +1100
      Re: Processing large CSV files - how to maximise throughput? Stefan Behnel <stefan_ml@behnel.de> - 2013-10-25 08:39 +0200
      Re: Processing large CSV files - how to maximise throughput? Chris Angelico <rosuav@gmail.com> - 2013-10-25 18:26 +1100
      Re: Processing large CSV files - how to maximise throughput? Dave Angel <davea@davea.name> - 2013-10-25 11:24 +0000
      Re: Processing large CSV files - how to maximise throughput? Chris Angelico <rosuav@gmail.com> - 2013-10-25 22:42 +1100
  Re: Processing large CSV files - how to maximise throughput? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-25 03:19 +0000
  Re: Processing large CSV files - how to maximise throughput? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-10-25 04:46 +0100
  Re: Processing large CSV files - how to maximise throughput? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-10-25 19:44 -0400
    Re: Processing large CSV files - how to maximise throughput? Roy Smith <roy@panix.com> - 2013-10-25 20:22 -0400
  Re: Processing large CSV files - how to maximise throughput? Walter Hurry <walterhurry@lavabit.com> - 2013-10-26 08:53 +0000

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