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[LDM #KWB-851882]: pqact issues reading pq file

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  • Subject: [LDM #KWB-851882]: pqact issues reading pq file
  • Date: Mon, 19 Aug 2013 09:51:52 -0600
Kevin,

That sounds like a good test. I wish the results were more definitive.

All processes that share the LDM product-queue should share the same 
memory-segment (i.e., the product-queue should only be in one place in memory).

> Steve
> 
> Thanks for the feedback.  A little update from yesterday on our end too.
> Brad and I setup LDM to run on our second ingest server as well as the
> primary Thursday night.  We did this for two reasons:
> 
> 1.  Eliminate the overhead of qpidd on the same box
> 2.  Not use edexBridge, just FILE the products to /data_store
> 
> We also created a separate, but equal, NFS partition for this test
> /data_store
> 
> Yesterday morning I investigated and saw the latency periods at the same
> time as cpsbn1(which was running LDM + qpidd), but the  severity was not as
> bad.  So, yesterday, we rebooted the DVB and I'll be checking on that
> today.  I'll let you know.  Also, in case I wasn't clear before -- what
> we're seeing isn't just with NEXRAD3, but also with other products at the
> same time.  We noticed it first and to the most extreme with that, but it
> isn't isolated.
> 
> However, it doesn't appear that the periods of latency are related to qpidd
> or edexBridge,although I can't say we've 100% eliminated that.
> 
> We have been focusing a little on our memory usage on these servers.  How
> many GB of RAM do you all suggest for a server running noaaportIngester +
> pqact?  I see they all read the ldm.pq into shared memory, and this gives
> the impression that 5GB are used just by those processes -- although it
> appears they all use the same shared memory segment, so it is really only
> 1G -- correct?
> 
> Thanks again in advance,
> 
> Kevin
> 
> --
> *Kevin P Johnson, RHCE™*
> Principal Engineer with Honors
> AWIPS Lead Systems Engineer
> Mission Operations & Services
> *Raytheon Company*
> 
> +301-495-2257   (office)
> +301-244-8575   (cell)
> address@hidden
> address@hidden
> 
> 
> 8401 Colesville Road
> Suite 800
> Silver Spring, MD 20910
> www.raytheon.com


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: KWB-851882
Department: Support LDM
Priority: Normal
Status: Closed