Kernel PPS processing
Gary E. Miller
gem at rellim.com
Wed Jun 29 23:45:14 UTC 2016
Yo Matthew!
On Wed, 29 Jun 2016 16:38:40 -0400
Matthew Selsky <Matthew.Selsky at twosigma.com> wrote:
> Measuring on this server via ntpq -p we were seeing offsets of +/-
> 3us without either of these two kernel parameters. With nohz=off,
> the offsets were +/- 1us. With both kernel parameters we see
> offsets too small for ntpq -p to measure.
Just rebooted my main Intel chimer with "intel_idle.max_cstate=0".
It was already using HZ=100
Wow. I thought something was wrong. My local clock offset (peerstats
file) has always been hanging around 100ppm. Stable to ±1ppm so I
figured that was normal.
After reboot the local clock offset started at 9ppm and has been slowyly
going down, now under 2ppm.
I made note of these setting in the gpsd-time-service-howto.txt
Anyone got a guess what the equivalent RasPi setting to turn off
power saving would be?
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
gem at rellim.com Tel:+1 541 382 8588
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 473 bytes
Desc: OpenPGP digital signature
URL: <http://lists.ntpsec.org/pipermail/devel/attachments/20160629/de9b62c6/attachment.bin>
More information about the devel
mailing list