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[LDM #VAP-368514]: Primary/alternate switching mixes in old data with new

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  • Subject: [LDM #VAP-368514]: Primary/alternate switching mixes in old data with new
  • Date: Mon, 23 Nov 2009 16:53:44 -0700
Art,

> The queue on iddrs3 is 8GB; I haven't monitored that system for age of the
> oldest products in the queue, but based on other systems I've looked at
> I'm guessing it ranges from ~3000-6000 seconds.
> 
> I set the max latency large so if there's an extended outage, we recover
> as much of the data in the upstream queue as possible.  That amount varys
> depending on the average size of the products in the queue, correct?  If I
> specify a latency larger than the available data in the queue, shouldn't
> it just reach back to the beginning of the queue?  When things are caught
> up, maxlatency shouldn't matter...

Odd things can happen when the "from" time in a data request is older than the 
oldest product in the queue.  Those latency spikes you're seeing are one of 
them.  The "from" time is controlled by the $offset parameter in the 
ldmadmin(1) configuration-file (etc/ldmadmin-l.conf).  This parameter should be 
less than or equal to the minimum residency-time of the product-queue.

Can you make your queue larger?

> Art
> 
> Arthur A. Person
> Research Assistant, System Administrator
> Penn State Department of Meteorology
> email:  address@hidden, phone:  814-863-1563

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: VAP-368514
Department: Support LDM
Priority: Normal
Status: Closed