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[LDM #QSF-677716]: ldm queue size (UNCLASSIFIED)

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  • Subject: [LDM #QSF-677716]: ldm queue size (UNCLASSIFIED)
  • Date: Tue, 03 Mar 2015 10:45:13 -0700
Jule,

The maximum size of an LDM product-queue is determined by the number of bits in 
the Posix "off_t" integer type. If that type has 32 bits, then the 
product-queue will be limited to about 2 GB. If, however, that type is 64 bits, 
then the limit will be very, very large (2^64 - 1 bytes).

So, it depends on what's called the "programming environment". Some 32-bit 
systems, nevertheless, support a programming environment in with an "off_t" is 
64 bits. By default, the LDM configuration-file attempts to find the compiler 
options that will enable this environment.

You received an error message because the product-queue library checks the size 
of an "off_t" at runtime.

Given the amount of data that you wish to retain, your best bet would be to use 
a 64-bit computer. Can you do that?

> Classification: UNCLASSIFIED
> Caveats: NONE
> 
> Hello,
> 
> Are there limits to the queue size for ldm?
> 
> We have a 3g queue and received the message "Size "4G" too big" when
> trying to increase the size.
> 
> Our issue is that we would like to centralize our ldm data acquisition
> (mainly from NWS River Forecast Centers) and can only store 2 hours of
> products in the 3g queue from just 3 RFCs.  As we expand to other RFC's,
> the product time within the queue would decrease.  Our preference would
> be for the centralized ldm server(s) to retain 24-48 hours in the queue.
> If 3g is the queue limit, are there other processes we could use to
> provide 48 hour backup to satellite offices?
> 
> Thanks,
> Jule Bartels
> 314-331-8737
> 
> Classification: UNCLASSIFIED
> Caveats: NONE


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: QSF-677716
Department: Support LDM
Priority: Normal
Status: Closed