[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[NOAAPORT #ZLV-851048]: LDM misses data on NOAAPORT via satellite

Hi,

re:
> Just an update on things.

Very good, I've been wondering how things are going for you!

re:
> I have gone through all the suggested changes and currently running on 
> 6.13.13.

Excellent.

re:
> I am still getting the same results with lots of missed data on the faster LDM
> box compared to my slower computer that I have the same LDM running on.  I am
> wondering if the 16 cores and having processes split up in such a way is 
> causing
> issues. 

This is highly unlikely.

re:
> I have watching the logging via a tail -f and just as an "un-scientific"
> view I have noticed it scrolls by noticeably slower on my "more powerful" 
> computer.

Hmm... this is quite strange indeed. I wonder if it would continue to
be the same if you let the listings continue for more time?

re:
> I am thinking of changing some BIOS settings for the CPUs. I have been working
> remotely since March so that will take a trip into the office which will not 
> be
> a simple process because of guidelines in place.

Which BIOS settings are you thinking of changing?

re:
> Does my current thinking make any sense?

Actually, no.

re:
> The dual core system handling things better than 16 cores?

Nope, this does not make sense.

Please remind me if both of your machines are being fed from the
same DVBS2 receiver (which I assume is Novra S300N)?  If they are,
I would investigate whether ther was some issue with the network
hub that is being used to send the UDP stream to multiple machines.
We found that we needed to use a very high quality network hub
to split our receiver output to multiple machines.  When we
were using commodity units (DLink 8-port Gbps hubs), a lot of
noise was being introduced into the systems.  After replacing
the hubs with high quality ones, our ingest quality improved
markedly.  When I talk about ingest quality, I am referring to
how many Gap messages and associated missed frames are logged
as this is the best measure for how well data is being processed
by the DVBS2 receiver(s).

If there there are different receivers feeding your two machines,
I would run the test of switching which machine each receiver is
sending data to.

Regardless of the number of receivers you have, I would investigate
the Ethernet cabling that is connecting the receiver to each machine
if the errors you are referring to are Gap messages and associated
missed frames.

Questions:

- Would you like to have a Google Meet to discuss your problems?

- are you willing to institute some summary Gap stat measuring
  so that we would have hard numbers on how well/poorly your
  data ingest is?

Cheers,

Tom
--
****************************************************************************
Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
----------------------------------------------------------------------------
Unidata HomePage                       http://www.unidata.ucar.edu
****************************************************************************


Ticket Details
===================
Ticket ID: ZLV-851048
Department: Support NOAAPORT
Priority: Normal
Status: Closed
===================
NOTE: All email exchanges with Unidata User Support are recorded in the Unidata 
inquiry tracking system and then made publicly available through the web.  If 
you do not want to have your interactions made available in this way, you must 
let us know in each email you send to us.