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[LDM #VOM-137597]: Use of pqexpire causing ldm to 'lock up'?

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  • Subject: [LDM #VOM-137597]: Use of pqexpire causing ldm to 'lock up'?
  • Date: Tue, 07 Mar 2006 13:44:03 -0700
Steven,

> We are trying to setup a script that will use pqexpire to throw away a
> product so that it can be resubmitted again before it falls out of the
> queue on its own.  What we have noticed is that if two pqexpire are
> started at nearly the same time, all activity to the ldm.pq seems to be
> locked out, meaning, no data is received and pqinsert also blocks and
> one of the pqexpire hangs as well.  We were using -w with pqexpire to
> wait for any region locks on the queue, but were wondering if this was
> possibly causing the problem.  Should -w not be used?

You're attempting to work-around the design of the LDM, which isn't something 
I'd recommend.  Can't you do something else like file the data-product in 
question so that you can act upon it at will?

Other than that, I'm not sure what to tell you because the exact behavior 
depends on the details.  Are you using pqexpire(1)'s  "-i 0" option?  How often 
are data-products being inserted?  How many inserters are there?  What's the 
operating system?  What's the LDM version?  What's the size of the 
product-queue?  What was the programming environment (i.e., what are the first 
3 lines in the "configure.log" file after the line about maximizing the 
programming environment)?

> Thanks again!
> 
> --
> Steven Danz
> Senior Software Development Engineer
> Aviation Weather Center (NOAA/NWS/NCEP)
> 7220 NW 101st Terrace, Room 101
> Kansas City, MO 64153-2371
> 
> Email: address@hidden
> Phone: 816.584.7251
> Fax:   816.880.0650
> URL:   http://aviationweather.gov/
> 
> The opinions expressed in this message do not necessarily reflect those
> of the National Weather Service, or the Aviation Weather Center.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: VOM-137597
Department: Support LDM
Priority: Normal
Status: On Hold