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Date: Wed, 14 Nov 2012 16:16:16 +0000
Subject: Re: creating size-limited tar files
From: andrea crotti <andrea.crotti.0@gmail.com>
To: d@davea.name
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Xref: csiph.com comp.lang.python:33345

2012/11/14 Dave Angel <d@davea.name>:
> On 11/14/2012 10:56 AM, andrea crotti wrote:
>> Ok this is all very nice, but:
>>
>> [andrea@andreacrotti tar_baller]$ time python2 test_pipe.py > /dev/null
>>
>> real  0m21.215s
>> user  0m0.750s
>> sys   0m1.703s
>>
>> [andrea@andreacrotti tar_baller]$ time ls -lR /home/andrea | cat > /dev/null
>>
>> real  0m0.986s
>> user  0m0.413s
>> sys   0m0.600s
>>
>> <snip>
>>
>>
>> So apparently it's way slower than using this system, is this normal?
>
> I'm not sure how this timing relates to the thread, but what it mainly
> shows is that starting up the Python interpreter takes quite a while,
> compared to not starting it up.
>
>
> --
>
> DaveA
>


Well it's related because my program has to be as fast as possible, so
in theory I thought that using Python pipes would be better because I
can get easily the PID of the first process.

But if it's so slow than it's not worth, and I don't think is the
Python interpreter because it's more or less constantly many times
slower even changing the size of the input..