[time-nuts] Linux time servers

Poul-Henning Kamp phk at phk.freebsd.dk
Fri May 15 16:02:54 UTC 2009


In message <20090515.095406.-1739011364.imp at bsdimp.com>, "M. Warner Losh" write
s:

>When FreeBSD switched from gcc 3.x to gcc 4.x, I did measurements of
>the ability of the kernel to track a PPS (also changes with the major
>revision of the kernel).  I found that there was no measurable
>difference between the different FreeBSD kernels I tested despite
>being built with a number of different compilers (3.4.5, 4.2.0 and
>4.1).  It turns out that the algorithms for steering the time aren't
>dependent on how fast the results are computed, but rather dependent
>on the results being computed correctly.  [...]

... which you can read more about in my paper from 2002:

	http://phk.freebsd.dk/pubs/timecounter.pdf

Poul-Henning

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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