Hello, I read this thread : http://article.gmane.org/gmane.linux.kernel.kernelnewbies/31239 and have a question about it that I hope somebody will answer :) 1) What exactly does it mean to say that "User space sees value x for HZ?" I mean, for kernel space, I can understand that if I do things like nanosleep() etc then the resolution with which I can sleep is determined by the value of HZ inside the kernel. (or so I think). But what does the value of HZ in user space mean? 2) I tried the following program at the end of the above message I get the following values : #include <unistd.h> #include <time.h> #include <stdio.h> int main() { struct timespec res; double resolution; printf("UserHZ %ld\n", sysconf(_SC_CLK_TCK)); clock_getres(CLOCK_REALTIME, &res); resolution = res.tv_sec + (((double)res.tv_nsec)/1.0e9); printf("SystemHZ %ld\n", (unsigned long)(1/resolution + 0.5)); return 0; } I get the values: UserHZ 100 SystemHZ 1000000000 This looks a bit too high to me? (My kernel version is 2.6.27/fedora core 10 , /usr/include/asm/param.h says that HZ is 100 ) Thanks a lot in advance :) ---------------------------------------------------------------------------------------------------------------------------------------- Primate evolution is the ultimate revenge of the nerds. (How the mind works, Steven Pinker) ---------------------------------------------------------------------------------------------------------------------------------------- -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
