[LinuxPPS] Recommendation / Re: Stats & architectures

[James Boddington]

Udo van den Heuvel wrote:
> James Boddington wrote:
>> Found http://lkml.org/lkml/2008/3/14/267 while looking for information about 
>> STA_NANO. Reading that thread it looks like what I said about the offset is 
>> changing. http://lkml.org/lkml/2008/3/14/273 is the post that caught my 
>> attention, do_adjtimex() will accept nano or micro depending whether STA_NANO 
>> is defined. STA_NANO also has a bit to do with how ntp is built.
> 
> What would I need to check with ntp source?

I used grep. One bit of code from ntp_loopfilter.c

#ifdef STA_NANO
                         ntv.offset = (int32)(clock_offset * 1e9 +
                             dtemp);
                         ntv.constant = sys_poll;
#else /* STA_NANO */
                         ntv.offset = (int32)(clock_offset * 1e6 +
                             dtemp);
                         ntv.constant = sys_poll - 4;
#endif /* STA_NANO */

clock_offset is declared as a double. Cases like this where ntp uses 9 digits 
if STA_NANO is defined and 6 other wise. There are also bits of code like that 
for jitter.

-- 
    James