Re: [chrony-users] Time offset on versions 3+ without hw timestamping

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Yes it's better that way ! Did not realise we could use -h like this..

Coming back to my isues with chrony 3 : I played a bit with cpu power management recently, at first to figure out first my problem with PPS sources, and found out that disabling the c-states would improve drastically chrony performances on my systems.

When i boot my systems with c-state disabled (kernel parameters processor.max_cstate=1 idle=poll ) my sources std dev can be devided by 5 to 10 with chrony 1.30

With chrony 3, changes are even more importants and i don't get any of those problems i was having before, test C is not failing anymore, std dev is minimal  (under 100ns on sources with hardware timestamping, with k/k on chrony side, 100x lower that when I was having without the kernel parameters) and peer delay is reduced by over 50us. 

Also, offset reported by my monitoring system are good again.

Would there be any way to get those performance without disabling c-states system-wide ? 



2017-09-11 14:13 GMT+02:00 Miroslav Lichvar <mlichvar@xxxxxxxxxx>:
On Mon, Sep 11, 2017 at 02:00:06PM +0200, Thibaut BEYLER wrote:
> Ok thanks, I tried with 'local" before and got very bad results, did some
> digging and turns out that was because I was having the same driftfile on
> both instance (probably the parameter isn't necessary on the server
> config), it's better now.
>
> I specified a custom sock as bindcmdaddress for each instance
>  (/var/run/chrony/chronyd_1.sock and /var/run/chrony/chronyd_1.sock) and a
> custom cmdport for sthe server instance.
>
> I can get chronyc to work with both instance, however ntpdata is not
> working on neitheir of them, i get "501 Not authorised", any idea ?

That means chronyc is not using the Unix domain socket. Did you
specify it with the -h option?

chronyc -h /var/run/chrony/chronyd_1.sock ntpdata

--
Miroslav Lichvar

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