[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [gpsd-dev] Updated docs on NTP segment management
From: |
Gary E. Miller |
Subject: |
Re: [gpsd-dev] Updated docs on NTP segment management |
Date: |
Wed, 25 Feb 2015 17:54:54 -0800 |
Yo Hal!
On Wed, 25 Feb 2015 11:03:15 -0800
Hal Murray <address@hidden> wrote:
> address@hidden said:
> > Yeah, I've already found some fields that I'd like to add to the
> > protocol, but didn't do it to not break the compatibility.
>
> What did you have in mind? I'd like to make sure we collect all the
> good ideas while this discussion is going on.
Well, the thing that had been byting me is the lack of a way to mark
an NTPSHM as 'in-use'. If I am not really careful I get gpsd and
ptp4l both trying to step on shmid NTP0.
The root:rooot/600 and root:root/666 perms thing also recently bit me.
We gotta do ntpd:ntpd/660 or gpsd:ntpd:660.
Another possibility, still noodling on it, would be to put a real
POSIX semaphore inside the SHM, so the slaves do not need to keep
polling, plus that give you a memory barrier for free.
> Would it have made sense to use the dummy slots in the current SHM?
> (assume we could find a way to avoid collisions)
Yes, similar to the nSec addition.
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97701
address@hidden Tel:+1(541)382-8588
- Re: [gpsd-dev] Updated docs on NTP segment management, (continued)
- Re: [gpsd-dev] Updated docs on NTP segment management, Miroslav Lichvar, 2015/02/23
- Re: [gpsd-dev] Updated docs on NTP segment management, Gary E. Miller, 2015/02/23
- Re: [gpsd-dev] Updated docs on NTP segment management, Harlan Stenn, 2015/02/23
- Re: [gpsd-dev] Updated docs on NTP segment management, Gary E. Miller, 2015/02/23
- Re: [gpsd-dev] Updated docs on NTP segment management, Miroslav Lichvar, 2015/02/25
- Re: [gpsd-dev] Updated docs on NTP segment management, Hal Murray, 2015/02/25
- Re: [gpsd-dev] Updated docs on NTP segment management,
Gary E. Miller <=
- Re: [gpsd-dev] Updated docs on NTP segment management, Hal Murray, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Gary E. Miller, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Miroslav Lichvar, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Eric S. Raymond, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Miroslav Lichvar, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Eric S. Raymond, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Hal Murray, 2015/02/27
- Re: [gpsd-dev] Updated docs on NTP segment management, Hal Murray, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Eric S. Raymond, 2015/02/26
- Re: [gpsd-dev] Updated docs on NTP segment management, Terje Mathisen, 2015/02/26