[CMake] Status/use of CMake on Cygwin

marco atzeri marco.atzeri at gmail.com
Mon May 20 05:50:52 EDT 2013


Il 5/20/2013 11:01 AM, Alan W. Irwin ha scritto:
> On 2013-05-20 07:51+0200 marco atzeri wrote:
>
>> the slowness at startup on cywin is mainly due the fork
>> implementation
>> http://cygwin.com/faq/faq-nochunks.html#faq.api.fork
>>
>> unfortunately windows makes a real fork implementation very inefficient.
>
> Hi Marco:
>
> Your explanation sounds reasonable since it appears all new processes
> are started with fork, but do you have a reference for that conclusion
> that gives more specifics? All the above URL says is that fork can be
> "a little slow" on Cygwin with no timing specifics.

"a littel slow" is an euphemism

$ while (true); do date; done | uniq -c
      11 Mon, May 20, 2013 11:38:10 AM
      11 Mon, May 20, 2013 11:38:11 AM
      11 Mon, May 20, 2013 11:38:12 AM
      11 Mon, May 20, 2013 11:38:13 AM
      11 Mon, May 20, 2013 11:38:14 AM
      11 Mon, May 20, 2013 11:38:15 AM
       8 Mon, May 20, 2013 11:38:16 AM
       6 Mon, May 20, 2013 11:38:17 AM

on Linux this is around 20-50 times faster.

We also noted that Windows 64 bit platforms are slower than
previously Windows 32 bit platforms

see
http://cygwin.com/ml/cygwin/2011-07/msg00354.html
and similar on cygwin mailing list.

>
> Alan
>
> __________________________
> Alan W. Irwin
>

Regards
Marco



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