[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [gpsd-dev] [PATCH] HOWTO: calculate the average GPS offset
From: |
Gary E. Miller |
Subject: |
Re: [gpsd-dev] [PATCH] HOWTO: calculate the average GPS offset |
Date: |
Mon, 21 Oct 2013 16:52:00 -0700 |
Yo Andy!
On Mon, 21 Oct 2013 19:43:10 -0400
Andy Walls <address@hidden> wrote:
> Days seems like too long.
I deploy a lot of servers. Some have good clocks, some not. Last year
I saw two servers ntpd could not converge on at all, after weeks. That
is when I converted to chronyd. YMMV.
And if you server goes though busy periods that will also delay getting
a god sync.
> The serial stream jitters *alot*.
hehehe, yeah.
> Looking at the peerstats for the GPSD/Shared Memory clock, and
> throwing out the initial 6000 seconds, I observed the following about
> the offset:
>
> Mean: -0.455
> Min: -0.495
> Max: -0.413
Is that PPS over USB or PPS over RS-232? That is within what I see
for PPS over USB, but I have seen better. If that is PPS over RS-232 then
something is wrong.
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97701
address@hidden Tel:+1(541)382-8588
signature.asc
Description: PGP signature
Re: [gpsd-dev] [PATCH] HOWTO: calculate the average GPS offset, Eric S. Raymond, 2013/10/22