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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: Tue, 13 Aug 2013 15:14:05 -0600
Kevin,

> I'd expect to see a spike in iowait times if there are struggles to write
> to any backend storage, NFS included -- I've not seen any indication of
> that in the sar logs I'm collecting.  That being said, knowing NFS and the
> slight overhead it brings here is the info
> 
> nas:/dataSTORE /data_store nfs
> rw,vers=3,rsize=65536,wsize=65536,hard,proto=tcp,timeo=600,retrans=2,sec=sys,addr=nas
> 0 0
> 
> Like I said before, it is a 1TB partition which is about 17% full

Rather than look at the performance metrics of the computer running the LDM, 
can you investigate the performance of the NFS server? It's possible, for 
example, that the NFS server needs more threads in order to handle the load 
being put on it.

Alternatively, can you write the NEXRAD3 data-product to a local disk instead 
of to an NFS-mounted partition? If the problem disappears, then the NFS-mounted 
partition is the bottleneck.

> --
> *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