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[LDM #TUN-623089]: LDM Duplicate Products

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  • Subject: [LDM #TUN-623089]: LDM Duplicate Products
  • Date: Fri, 07 Nov 2014 13:53:42 -0700
Bob,

> Thanks for the information.  I do reconcile the queue/latency with "decrease 
> maximum latency" as my reconciliation mode on all LDM servers.  On the 
> downstream server, the registry has my max latency as 685s.  The "pqmon -S" 
> has my minimum residence time as 2300s.  With that being in order, am I 
> correct in assuming that retransmission of the same product is my problem?

Given that your maximum acceptable latency is less than your minimum residence 
time, then your problem is that products are being retransmitted after a time 
interval that's greater than your minimum residence time; consequently, the 
products no longer exist in the queue and are being accepted.

> If a retransmitted product is the same as another copy is sitting in queue 
> (with only a different sequence number), does it follow that the sequence 
> number must actually be part of the product's data and therefore part of the 
> checksum -- otherwise it would be rejected?

The sequence number is part of a data-product's metadata and isn't used to 
compute the checksum. The problem is the time between retransmissions is 
greater than the minimum residence time.

The solution would be to increase the minimum residence time beyond the 
retransmission time-interval by either increasing the queue-size parameters or 
decreasing the amount of data going into the queue.

> Bob

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: TUN-623089
Department: Support LDM
Priority: Normal
Status: Closed