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[LDM #OAO-873149]: Re: RPCCDS LDM Feedtype Enhancement

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  • Subject: [LDM #OAO-873149]: Re: RPCCDS LDM Feedtype Enhancement
  • Date: Mon, 31 Mar 2008 13:27:11 -0600
Gini,

> Can you help with the following issue that our developer has encountered in 
> porting the NWS Radar3 delivery system from Onnicast to LDM-6.6.5 protocol?
> 
> Dave wrote:
> > It appears that the LDM Receiver file processing
> > utility 'pqact' functions on 30 second intervals resulting in file
> > availability lags up to that amount of time for any particular product
> > file transmission from the upstream server.  Our near-real-time service
> > level objective cannot tolerate that much delay.  Gini, if you could take
> > this up with Unidata it would be appreciated (we are experimenting with
> > the LDM-6.6.5 release).

This sounds familiar.

Any "pqact" process *must* be started as a result of an EXEC
entry in the LDM configuration-file (etc/ldmd.conf); otherwise,
the process won't receive the CONT signals that are sent to
every process in the LDM process-group to indicate that a
data-product has been added to the product-queue.  See
<http://www.unidata.ucar.edu/software/ldm/ldm-current/basics/ldmd.conf.html#EXEC>
<http://www.unidata.ucar.edu/software/ldm/ldm-current/basics/programs.html#pqact>,
and
<http://www.unidata.ucar.edu/software/ldm/ldm-current/basics/behavior.html#downstream>
for more information.

Dave, you can contact us directly by sending email to
<address@hidden>.

> Thanks
> Gini Galvin
> Internet Specialist
> NWS/TOC
> 301 713 0882 x 176

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: OAO-873149
Department: Support LDM
Priority: Normal
Status: Closed