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[LDM #COH-141109]: Question about multiple pqact processes to handle different feeds

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  • Subject: [LDM #COH-141109]: Question about multiple pqact processes to handle different feeds
  • Date: Fri, 03 Nov 2006 12:43:34 -0700
Pete,
 
> We have noticed recently on f5.aos.wisc.edu that during times of
> high data throughput (particularly when the GFS grib1 and grib2
> data are coming through on CONDUIT) that our DDPLUS data saved to
> disk falls behind.
> 
> Looking at the products coming in via ldmadmin watch, it appears
> that the products are coming in in a timely manner, but the pqact
> process is falling behind at parsing through the queue.
> 
> I had the thought today that I could run a second pqact process
> with a different pqact.conf that would only handle DDPLUS data,
> and take the DDPLUS out of the main pqact. That way the DDPLUS
> pqact could skip all the other data and just handle the DDPLUS,
> hopefully quicker.  Does this make sense?  Think it would solve
> this problem (if that is indeed the problem?)

That's a good idea.  A pqact(1) process matches every data-product
that it gets with every entry in its configuration-file.  Consequently,
the fewer matches it has to do, the less CPU it uses.  If you're going
to do this, however, then be sure to add feedtype and prodoct-identifier
patters to each invocation of pqact(1) by an EXEC entry in the LDM
configuration-file.  The objective is to ensure that every product
that a pqact(1) processes sees is matched by something in its
configuration-file.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: COH-141109
Department: Support LDM
Priority: Normal
Status: Closed