RE: gettimeofday being faster than getpid?

Jeremy Fitzhardinge (jeremy@goop.org)
Sun, 07 Nov 1999 13:04:54 -0800 (PST)

On 02-Nov-99 Pavel Machek wrote:
> Hi!
>
> I did some tests, and when I replace getuid() or getpid() with
> gettimeofday(), it actually gets faster.
>
> getuid takes 14usec on my machine.
> gettimeofday takes 4usec on my machine.
>
> I think that is pretty strange.
> Pavel
>
>#include <sys/time.h>
>#include <unistd.h>
>
> void main(void)
> {
> struct timeval tv1, tv2, tv3;
>

Try putting getpid() here too.

> gettimeofday(&tv1, 0);
> getuid(); <--- here
> gettimeofday(&tv2, 0);
>
> printf("Time1: %d:%d\n", tv1.tv_sec, tv1.tv_usec);
> printf("Time2: %d:%d\n", tv2.tv_sec, tv2.tv_usec);
> }

The first gettimeofday will warm the caches. If I pre-call getpid(), I get the
same speed for both.

J

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