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[LDM #XKS-398652]: request for enlightenment

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  • Subject: [LDM #XKS-398652]: request for enlightenment
  • Date: Mon, 29 Sep 2014 17:36:35 -0600
Hi Steve,

Steve Emmerson asked me to comment on:

> On a somewhat related subject, our LDM is on a 32 bit operating system
> currently. It's on-the-list to upgrade to a 64 bit OS.

OK, that is where most people are heading.

re:
> Is it a "bad
> thing" to have a queue larger than 2 GB on a 32 bit OS?

If you built the LDM with large file support (the default when running
'configure' with no options), then there is no additional overhead
having an LDM queue larger than 2G.  If, on the other hand, you built
the LDM _without_ large file support (one would need to specify the
'--disable-max-size' flag when running 'configure'), then you will
likely not be able to specify a queue larger than 2G depending on
how your OS defines OFF_T.  Interestingly, the LDM built without
large file support is a bit faster than if was built with large
file support on 32-bit systems.  There doesn't see to be much of
a difference on 64-bit systems.

re:
> And what is the
> recommended queue size for a NOAAPort based machine getting all 5
> channels?

Assuming that you are saying that your machine will be ingesting 
NOAAPort, I have a couple of comments:

- Wednesday the old NOAAPort broadcast is scheduled to be turned
  off as it is the end of the 45-day dual illumination period
  where both the original and expanded broadcasts have been running

  If you have not yet attended to moving to the new expanded NOAAPort
  broadcast, you should do so as soon as you can!

- the expanded NOAAPort broadcast has 8 channels, not 5: PIDs 101-108,
  inclusive

- we are increasing the size of the LDM queues on our NOAAPort ingest
  machines from 2G to 8G

  The reason for doing this is to eliminate more of the rebroadcast
  products that we have seen increasingly in the era of the expanded
  NOAAPort broadcast.  Of course, to increase the queue size we needed
  to have 64-bit ingesters and more RAM.

I hoped that this helps!

Cheers,

Tom
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Ticket Details
===================
Ticket ID: XKS-398652
Department: Support LDM
Priority: Normal
Status: Closed