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[LDM #MSE-433853]: Hourly Statistics of LDM feed

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  • Subject: [LDM #MSE-433853]: Hourly Statistics of LDM feed
  • Date: Thu, 10 Aug 2017 13:32:57 -0600
Carol,

When a data-product is created, its "origin" field is set to the hostname
of the local host. When the data-product is first inserted into the LDM
product-queue its origin field will have this value.

Whenever a downstream LDM receives a data-product and before it inserts the
data-product into the product-queue, it modifies the product's origin field
by either appending the string "_v_<upstream>" (where <upstream> is the
name of the host from which the product was received) or modifying that
suffix to reference the upstream host if the suffix already exists.

The fact that the origin field in question has the value
"herbie-amrc.ssec.wisc.edu_v_herbie-amrc.ssec.wisc.edu" means that those
data-products were created on Herbie and received by a downstream LDM on
Herbie from an upstream LDM on Herbie.

This could happen if Herbie's LDM configuration-file contained a REQUEST
entry for products from Herbie.

Why one would want to do this is beyond me. I note, however, that this only
occurred during one hour. Perhaps someone was fiddling with the
configuration-file?

> I was thinking more about the
> herbie-amrc.ssec.wisc.edu_v_herbie-amrc.ssec.wisc.edu bar in the plot.
> 
> http://rtstats.unidata.ucar.edu/cgi-bin/rtstats/iddstats_vol_nc?EXP+herbie-amrc.ssec.wisc.edu
> 
> Are these simply products that are created on herbie and inserted into
> herbie's queue? But then this doesn't make sense because Tom explained
> that this graph is only for data is being received, not sent. Maybe I'm
> not understanding what you mean by saying "sent".
> 
> It's also odd that the graph is showing a spike of 8.5 MB at about 00
> UTC. The data that is created on herbie is sent every hour and the
> amount of data is about 35 KBs.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: MSE-433853
Department: Support LDM
Priority: Normal
Status: Closed
===================
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