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[LDM #DHW-503620]: Question about how pqact.conf is triggered by incoming data?

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  • Subject: [LDM #DHW-503620]: Question about how pqact.conf is triggered by incoming data?
  • Date: Wed, 27 Jun 2012 15:18:04 -0600
Robert,

> Full Name: Robert Gordon
> Email Address: address@hidden
> Organization: Precision Wind Inc.
> Package Version: 6.10.1
> Operating System: Linux x86_64
> Hardware:
> Description of problem:
> 
> We are encountering an issue with our pqact.conf file, and it appears to
> be related to how LDM fires off an EXEC command defined with pqact.conf,
> before the entirety of the file being downloaded by LDM is complete.
> 
> The example would be that we receive a number of very large raw data
> files that require at least a minute to fully download.  However,
> as soon as LDM detects the file is being downloaded, it immediately
> fires off an EXEC line in our pqact.conf file, even if the file being
> downloaded hasn't fully completed.   This creates situations where LDM
> then tries to loop back and fire off the EXEC line in pqact.conf again,
> because it sees the incoming file as still 'in play'.
> 
> Is there a way for LDM to detect if a file has been fully downloaded,
> before it triggers additional steps within the pqact.conf file?

A downstream LDM process holds a lock on the region in the product-queue into 
which a data-product will be written. Until this lock is released when the 
data-product is completely written, no pqact(1) process will see the 
data-product. It's unlikely, therefore, that your pqact(1) process is acting on 
data-products before they're available.

How many pqact(1) processes do you have?

Does each pqact(1) process have its own configuration-file?

Could you send me the relevant entries in your pqact(1) configuration-file?

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: DHW-503620
Department: Support LDM
Priority: Normal
Status: Closed