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[LDM #WSP-283484]: latency between receiving and writing NNEXRAD

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  • Subject: [LDM #WSP-283484]: latency between receiving and writing NNEXRAD
  • Date: Mon, 22 Oct 2007 13:14:49 -0600
Gerry,

> Right now, they look similar: no latency.  I *think* I did this test
> last night... and over the weekend, and they were also similar/ideal
> with no latency, but writing the files to disk was delayed.  I've just
> flushed the queue and restarted (another issue) and the latency is at
> the 1 hr level but I'll keep watching it...

In that case, the problem is probably with the "pqact" process
that writing the files.  You can put that process into verbose
logging mode by sending it a USR2 signal.  It will then tell
you the delay in processing each data-product.  Send it two
more USR2 signals to revert logging to the original mode.

Do the relevant "pqact" configuration-file entries use the 
"-flush" or "-close" options?  If not, then there's no telling
when the data will hit the disk.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: WSP-283484
Department: Support LDM
Priority: Normal
Status: Closed