cosmopolitan/examples/nanosleep_test.c
Justine Tunney b407327972
Make fixes and improvements
- clock_nanosleep() is now much faster on OpenBSD and NetBSD
- Thread joining is now much faster on NetBSD
- FreeBSD timestamps are now more accurate
- Thread spawning now goes faster on XNU
- Clean up the clone() code
2022-11-08 10:11:46 -08:00

44 lines
1.6 KiB
C

#if 0
/*─────────────────────────────────────────────────────────────────╗
│ To the extent possible under law, Justine Tunney has waived │
│ all copyright and related or neighboring rights to this file, │
│ as it is written in the following disclaimers: │
│ • http://unlicense.org/ │
│ • http://creativecommons.org/publicdomain/zero/1.0/ │
╚─────────────────────────────────────────────────────────────────*/
#endif
#include "libc/assert.h"
#include "libc/calls/struct/timespec.h"
#include "libc/stdio/stdio.h"
#include "libc/sysv/consts/clock.h"
/**
* @fileoverview shows how accurate clock_nanosleep() is
*/
int main(int argc, char *argv[]) {
long i, ns;
struct timespec x, y, w;
timespec_sleep(timespec_fromnanos(0)); // warmup
printf("\nrelative sleep\n");
for (i = 0; i < 28; ++i) {
ns = 1l << i;
x = timespec_real();
timespec_sleep(timespec_fromnanos(ns));
y = timespec_real();
printf("%,11ld ns sleep took %,ld ns\n", ns,
timespec_tonanos(timespec_sub(y, x)));
}
printf("\nabsolute sleep\n");
for (i = 0; i < 28; ++i) {
ns = 1l << i;
x = timespec_real();
timespec_sleep_until(timespec_add(x, timespec_fromnanos(ns)));
y = timespec_real();
printf("%,11ld ns sleep took %,ld ns\n", ns,
timespec_tonanos(timespec_sub(y, x)));
}
}