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Re: 20201028: Re: [conduit] CONDUIT LDM Clock Drift

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  • Subject: Re: 20201028: Re: [conduit] CONDUIT LDM Clock Drift
  • Date: Wed, 28 Oct 2020 17:41:21 +0000

Thanks, Tom. Yes, this should help get this one resolved... once we're out of CWD mode. The NCEP Dataflow and NCO folks have lots on their plates, as always.

     -Bob

On Wed, Oct 28, 2020 at 5:20 PM Tom Yoksas <address@hidden> wrote:
Hi Bob and Daryl,

Both we and Pete Pokrandt (UWisconsin/AOS) have reported the clock
drift on the NCEP machines that are the source of the feed.  I,
in particular, have let them know that the drift has affected at
least a couple of sites that had configured their LDMs (via the
LDM registry) to minimize latency (meaning throw away any products
that have a latency greater than their configured amount).  We
were told in September that the clock drift problem was scheduled
to be fixed in October, and I misinterpreted this to mean that it
would be addressed in early October.

If you were not already aware, more than one NCEP person is subscribed
to the address@hidden email list.  Perhaps your postings
will help move addressing the problem up the list of things to do.

Cheers,

Tom

On 10/28/20 11:09 AM, Bob Lipschutz - NOAA Affiliate via conduit wrote:
> We see the same here at NOAA/GSL. Here is our CONDUIT latency trace for
> the last 6 months. The drift started in early May. Prior to that,
> latency was flat and <10s.
>
> CONDUIT_latency_20201028.png
>
>
>      Bob Lipschutz
>      NOAA/ESRL/Global Systems Lab (formerly GSD)
>      IT Services/Data Services Group
> address@hidden <mailto:address@hidden>
>
> On Wed, Oct 28, 2020 at 4:55 PM Herzmann, Daryl E [AGRON]
> <address@hidden <mailto:address@hidden>> wrote:
>
>     Greetings (emailing the right list this time!),
>
>     It has been mentioned a few times on this list that there is a clock
>     drift issue with the CONDUIT LDM feed emitting from NCO/IDP.  I'd
>     like to ping this issue again and see if NCO can please check that
>     system clocks are being synced there.  The attached plot of feed
>     latency shows the building of latency with time from my monitoring,
>     which is a tell tale sign of clock drift.
>
>     thanks!
>     daryl
>
>     --
>     /**
>       * daryl herzmann
>       * Systems Analyst III -- Iowa Environmental Mesonet
>       * https://mesonet.agron.iastate.edu
>       */
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