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[LDM #YEX-392060]: ldm question

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  • Subject: [LDM #YEX-392060]: ldm question
  • Date: Mon, 30 Mar 2015 10:44:06 -0600
Michael,

> Hi Steve,
> That initial hour and forty minutes is our queue getting completely
> rebuilt. We rebooted the server and the queue is in memory.

By "the queue is in memory" I assume you mean that the memory-mapped 
product-queue is small enough that it can be completely held in physical memory.

> The data is
> still coming in, and at this point appears to be about five minutes old.
> The file name time stamps are about that far behind the server clock.
> Continuing to monitor to see if the feed stops or if there's an increase in
> latency.

In our experience, file-names are only a rough indication of latency. A better 
indicator is to compare the creation-times of data-products against the 
log-message timestamp from either an `ldmadmin watch` or a `notifyme` to the 
(default) local host.  For example:

/opt/ldm% ldmadmin watch -f 'IDS|DDPLUS'
(Type ^D when finished)
Mar 30 16:44:09 pqutil INFO:      254 20150330164409.090 IDS|DDPLUS 52846168  
SXOM33 EUMS 301640 RRX
Mar 30 16:44:09 pqutil INFO:      265 20150330164409.090 IDS|DDPLUS 52846169  
SXOM33 EUMS 301640 RRX
Mar 30 16:44:09 pqutil INFO:      254 20150330164409.090 IDS|DDPLUS 52846170  
SXOM33 EUMS 301637 RRX
Mar 30 16:44:09 pqutil INFO:      261 20150330164409.090 IDS|DDPLUS 52846171  
SXOM33 EUMS 301639 RRX
Mar 30 16:44:09 pqutil INFO:      254 20150330164409.090 IDS|DDPLUS 52846172  
SXOM33 EUMS 301636 RRX
Mar 30 16:44:09 pqutil INFO:      259 20150330164409.090 IDS|DDPLUS 52846173  
SXOM33 EUMS 301637 RRX
Mar 30 16:44:09 pqutil INFO:      111 20150330164409.090 IDS|DDPLUS 52846174  
SXOM33 EUMS 301639 RRX
Mar 30 16:44:09 pqutil INFO:     6356 20150330164409.092 IDS|DDPLUS 52846175  
SRUS43 KDVN 301644 /pRVADVN

A comparison of the log-message timestamps in the above against the associated 
data-product creation-times shows that the data-products were received within 1 
second of their creation.

> Michael
> 
> --
> Michael K. Johnson
> National Weather Service
> Central Region Headquarters
> Kansas City, MO
> 816-268-3160


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: YEX-392060
Department: Support LDM
Priority: Normal
Status: Closed