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[LDM #XXW-990118]: LDM - Not your average latency problem

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  • Subject: [LDM #XXW-990118]: LDM - Not your average latency problem
  • Date: Mon, 16 Oct 2006 11:26:31 -0600
Mike,

> I've been having trouble getting data to Sonoma tech. Here is a summary of 
> the symptoms and actions I've taken.
> 
> - rtstats 
> Sonoma:http://www.unidata.ucar.edu/software/idd/rtstats/siteindex.php?derecho.sonomatech.com
> Rossby:http://www.unidata.ucar.edu/software/idd/rtstats/siteindex.php?rossby.met.sjsu.edu
> - When I restart both LDMs, data flows freely, and then something gets gummed 
> up....then it kind of comes and goes.
> - I have reduced the feed to only DDS, UNIWISC, and FNEXRAD. This has no 
> effect.
> - I get latency on DDS, not just large product feeds
> - If I increase the feeds I can get Volume as high as 200 MB per hour, which 
> is near their pipe limit, but it fades and then comes and goes.
> - ldmd.log has no entries for the last 12 hours on both sonoma tech's end and 
> on my machine rossby. Before that there is an occasional "exited with status 
> 1" but in general the data that comes in decodes fine.
> - I did recompile ldm at Sonoma with "-disable max queue size" because I 
> thought that might have been the culprit...no help.
> - "ldmping" never shows a problem
> (BTW- How do I send output from ldmping to a file? I was unable to redirect 
> output.)
> - in the old LDM were able to configure mtime and otime I think it was. Do we 
> still have that ability somewhere?
> 
> At this point I'm looking for other possibilites. I have read through many of 
> the old latency emials, but nothing seems to match my issue. Does the 
> particular latency pattern indicate anything? It did not look like packet 
> shapping to me.
> 
> Anyhow, thanks for any insight, or please let me know what diagnostics I can 
> forward. If someone wants to take the plunge I have the log in for Sonoma 
> tech's machine.

OK, we'll take the plunge.  Please send me the login information for Sonoma 
Tech's LDM computer (hostname, username, password).  Call me at 303-497-8648 to 
give me the password.

Do I have your permission to modify (and possibly reconfigure and restart) both 
Rossby's and Sonoma Tech's LDM-s?

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: XXW-990118
Department: Support LDM
Priority: Normal
Status: On Hold