[LDM #RTA-128892]: Interpretation of "INFO sending" and "error.c:err_log:236"

Hi Gregory,

> I've searched the LDM archives for "INFO sending" and "error.c:err_log:236"
> and the best I can determine is the error means the product referenced in
> the upstream LDM was NOT successfully received by the downstream LDM.  Is
> this a correct interpretation or are there more reasons/information
> regarding this error?

The "sending" message is printed just before the product is put on the wire. 
It's not an error. If an error does occur, there will be a subsequent error 
message.

It's unfortunate that the module that writes this message is named "error".

> Also, if a downstream LDM queue is too small, are there any particular log
> entries in the downstream LDM or upstream LDM that would point to a queue
> size being too small?

Neither the upstream log file nor the downstream log file would have anything.

A queue is sized correctly if the minimum age of a product in the queue is 
greater than the maximum latency parameter in the LDM registry. One way to 
verify this is to use the "ldmadmin addmetrics" and "ldmadmin plotmetrics" 
commands (see 
https://www.unidata.ucar.edu/software/ldm/ldm-current/basics/monitoring.html#metrics
 for more information). Another way is to examine the "minVirtResTime" 
parameter in the output from the command "pqmon -S" (see the man(1) page for 
more information).

The maximum latency parameter sets the length of time the LDM can be offline 
without missing anything.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: RTA-128892
Department: Support LDM
Priority: Normal
Status: Closed
===================
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