RE: Wall clock accuracy

Sorry for double post...
=20

-----Original Message-----
From: Eugene Surovegin [mailto:ebs@ebshome.net]=20
Sent: Tuesday, August 09, 2005 11:41
It's not small drift (I usually have clock accuracy within +-50ppm),=20
but still is much less than maximum 1024ppm NTPD can deal with.

My bigger problem with the walltime is that time_nsec should have been
1000000, not 999848 to begin with. If it had been, I would probably
never even have noticed it.

The thing is that that value is set based on a value I cannot find any
reference as how was chosen. Looks to be a leftover when porting PPC
fron i386 once upon a time.

time_nsec basically gets is value (via some macros) from
CLOCK_TICK_RATE, which is defined in asm-ppc/timex.h to be 1193180

In my opinion, time_nsec should have been calculated based on the actual
clock input rate to begin with (like in calibrate_decrementer()).

On Tue, Aug 09, 2005 at 12:04:10PM -0500, Rune Torgersen wrote:

My bigger problem with the walltime is that time_nsec should have been
1000000, not 999848 to begin with. If it had been, I would probably
never even have noticed it.

The thing is that that value is set based on a value I cannot find any
reference as how was chosen. Looks to be a leftover when porting PPC
fron i386 once upon a time.

time_nsec basically gets is value (via some macros) from
CLOCK_TICK_RATE, which is defined in asm-ppc/timex.h to be 1193180

In my opinion, time_nsec should have been calculated based on the actual
clock input rate to begin with (like in calibrate_decrementer()).

Fair enough, why then instead of fixing the root cause you are making 
ugly workarounds :) ?

-- 
Eugene