linux system timing

david (sector2@ihug.co.nz)
Sun, 05 Sep 1999 05:35:39 +0000


we need a better time system for linux glibc
a double float value
struct {
double count ;
double clocks_per_sec ;
}
so time = count / clocks_per_sec

64 bit float max = 2^64 / clockpersec = 5.2704 * 10^10 sec =
1675.855 years
128 bit float max = 2^128 / clockpersec = 9.7223 * 10^29 sec = 3.091407
* 10^22 years
a 128 bit float can be use for faster cpu's
for intel we can get this by useing the 32 bit counter (clocked at core
speed) inside the cpu
ge
a PII 350 Mhz

1 count = 1 / (350 * 10^6) = 2.857142857 ....... ns
witch will rollover every
time = count / cpu core clk = 2^32 / (350 * 10^6) = 12.27133513
sec
when rollover is achieved it can interrupt witch will count the hi bits
(32 - 127) of the value

is someone all ready doing this

linux can be the beast computing tool lets make it so

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