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[LDM #AFT-567406]: GOES-17 data filing question

Hi Mike,

re:
> As you noticed, something really bad happened...started Friday and
> continued into the weekend.

And, it is apparently continuing.  The latency+volume plots for
feeds being REQUESTed by vulcan are now exhibiting what a "classic"
signature for packet shaping - data in low volume feeds gets delivered
with acceptable (but not great in vulcan's case) latencies while high
volume feeds latencies climb to values that exceed the maximum latency
parameter that is set in the LDM registry.

re: 
> Ironically this issue was much worse than what
> prompted me to investigate in the first place.

I think that there was one thing going on when you first contacted
us, and that was a result of the LDM queue being much too small
for the feeds being REQUESTed, and now you are facing a different
problem altogether.

re:
> I was turning feeds on and
> off though too, so volumes can be a bit misleading.

OK, but the comparison in latencies seen in the CONDUIT feed
(which I presume is still a 5-way split) and those for the
very low volume IDS|DDPLUS feed (a feed which also has very
small products) is what we have come to know as a classic
signature for artificial bandwidth limiting or packet shaping.

re:
> These stats are updating each minute.  Vulcan metrics only started this
> morning.  Charney on Friday 11/01.
> http://www.met.sjsu.edu/weather/images/vulcan/
> http://www.met.sjsu.edu/weather/images/charney/

The load average plot makes me ask what else is running
on vulcan?  And, why wasn't the same thing(s) running
between 2 and 14 UTC?

Speaking of load average, it is interesting that the
amount of data in the queue went up to near maximum
overnight.

re:
> We'll see how things look moving forward.

They don't look good this morning...

Cheers,

Tom
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Ticket Details
===================
Ticket ID: AFT-567406
Department: Support LDM
Priority: Normal
Status: Closed
===================
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