From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Sat,  4 Sep 2010 00:58:09 -0700
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From: Akshat Kumar <akumar@mail.nanosouffle.net>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: Re: [9fans] too many system calls.
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Is ratrace usable on native Plan 9 (I understand it's in use on 9vx
thus far)? I don't see a /proc/n/syscall file for any of my processes;
is there some kernel patch for this?


Thanks,
ak

On Fri, Sep 3, 2010 at 10:14 PM, ron minnich <rminnich@gmail.com> wrote:
> Glibc /bin/date on Linux runs around 140 system calls. A quick pass
> with ratrace shows that plan 9 /bin/date has 10.
>
> The conclusion is clear: plan 9 date has way too much overhead. It's
> 1/14 the number of system calls of Glibc; why's it so big?
>
> A quick pass on getpid() fixes the problem:
>
> #include =A0 =A0 =A0 =A0<u.h>
> #include =A0 =A0 =A0 =A0<libc.h>
> #include =A0 =A0 =A0 =A0<tos.h>
>
> int
> getpid(void)
> {
> =A0 =A0 =A0 =A0return _tos->pid;
> }
>
> Now we're down to seven system calls. 1/20 of glibc. Much better! :-)
>
> ron
>
>