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[OT] Re: fork() 50 times slower on some Linux kernels?

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Sorry, would have redirected this to a Linux or Unix group
but too much of the original information has been snipped
to be of any use over there, thus only the [OT] markers...

To the OP: please repost on comp.os.linux.development.apps
or comp.unix.programmer or similar where it would be on-
topic.

Kaz Kylheku <kaz@kylheku.com> wrote:
> On 2012-01-09, Elmar <elmar.krieger@gmail.com> wrote:
> > Interestingly, the slowness seems to be kernel dependent.

> How can you conclude that, when at the same time you are changing
> these variables:

> - architecture (x86_64 vs ia32)
> - hardware (different box)
> - different distro (CentOS vs Fedora)

I guess the worrying thing is the difference it seems make
if the memory is set or not. On my system (but with a 3.0
kernel) I also see a difference, but at a much smaller scale
- when the 500MB are set to 0 the system() call takes about
15 ms (what the OP called "instantly";-) while without it's
only 2.5 ms (both rather consistently). Not easily explained
when assuming a simple COW-behaviour on fork. If this would
be a Linux group I might even be tempted into booting an ol-
der kernel to see what a difference that makes on the exact
same hardware;-)
                         Regards, Jens
-- 
  \   Jens Thoms Toerring  ___      jt@toerring.de
   \__________________________      http://toerring.de

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fork() 50 times slower on some Linux kernels? Elmar <elmar.krieger@gmail.com> - 2012-01-09 12:25 -0800
  Re: fork() 50 times slower on some Linux kernels? Ian Collins <ian-news@hotmail.com> - 2012-01-10 09:41 +1300
  Re: fork() 50 times slower on some Linux kernels? Kaz Kylheku <kaz@kylheku.com> - 2012-01-09 21:32 +0000
    [OT] Re: fork() 50 times slower on some Linux kernels? jt@toerring.de (Jens Thoms Toerring) - 2012-01-09 22:12 +0000
      Re: [OT] Re: fork() 50 times slower on some Linux kernels? Kaz Kylheku <kaz@kylheku.com> - 2012-01-09 22:32 +0000
        Re: [OT] Re: fork() 50 times slower on some Linux kernels? Ian Collins <ian-news@hotmail.com> - 2012-01-10 11:56 +1300
  Re: fork() 50 times slower on some Linux kernels? Stephen Sprunk <stephen@sprunk.org> - 2012-01-09 16:11 -0600
    Re: fork() 50 times slower on some Linux kernels? Kaz Kylheku <kaz@kylheku.com> - 2012-01-09 22:30 +0000
      Re: fork() 50 times slower on some Linux kernels? Stephen Sprunk <stephen@sprunk.org> - 2012-01-09 17:20 -0600
        Re: [OT] fork() 50 times slower on some Linux kernels? jt@toerring.de (Jens Thoms Toerring) - 2012-01-09 23:57 +0000
          Re: [OT] fork() 50 times slower on some Linux kernels? Kaz Kylheku <kaz@kylheku.com> - 2012-01-10 00:22 +0000
            Re: [OT] fork() 50 times slower on some Linux kernels? Stephen Sprunk <stephen@sprunk.org> - 2012-01-09 20:39 -0600
              Re: [OT] fork() 50 times slower on some Linux kernels? William Ahern <william@wilbur.25thandClement.com> - 2012-01-09 19:43 -0800
                Re: [OT] fork() 50 times slower on some Linux kernels? Stephen Sprunk <stephen@sprunk.org> - 2012-01-10 00:31 -0600
          Re: fork() 50 times slower on some Linux kernels? Elmar <elmar.krieger@gmail.com> - 2012-01-11 14:39 -0800
        Re: fork() 50 times slower on some Linux kernels? Nobody <nobody@nowhere.com> - 2012-01-10 23:07 +0000

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