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[LDM #QYR-744357]: increase Q size

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  • Subject: [LDM #QYR-744357]: increase Q size
  • Date: Fri, 27 Jul 2012 12:36:29 -0600
Virginia,

> So LDM is mapping of LDM Q file to Memory ?

Yup. Later version memory-map the product-queue better than earlier versions.

> I'm unclear how an LDM upgrade would work around the mmap restrictions on
> 32 bit system.
> But are you saying we could try LDM upgrade to 6..9.8 or later that would
> allow us to work around any restrictions in mapping?

Later versions of the LDM allow you to obtain as large a product-queue as is 
possible on the system in question. The actual limit depends on the 
"programming environments" that are available. Some 32-bit systems nevertheless 
support large files (files larger than 4 GB).

> We could add more memory over 4GB -- but then I am told we are facing
> system limit on recognition of the new Memory that would mean a kernal
> patch.
> 
> We are building 64 bit replacements but  right now we just want to reduce
> latency on these old systems.  Two upstream feeders have 4GB queues and we
> think that increasing our queues to match would reduce latency.

I don't think a larger queue will reduce latency, which is the difference in 
time between when a product is created and when it arrives.

> Thanks
> Virginia

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: QYR-744357
Department: Support LDM
Priority: Normal
Status: Closed