Memory in XP and Vista

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Fri, 01/07/2011 - 06:34 pm

Hello,

I wrote a file importer procedure in IGOR for our recordings data that should read files 500 MB and larger. I have a 2 Ghz 2GB DDR2 RAM Vista computer and everything imports fine (IGOR 6.21). On my XP Professional machine I have 3 GB DDR3 RAM and I get an Out Of Memory error (Igor 6.12). Upgrading the Igor 6.12 to 6.21 is an issue right now because there a small incompatibility using NVAR.

Is the XP computer using virtual memory differently? Is there a setting in IGOR or Windows that can fix this?

Thank you,

Max
On a 64-bit Windows OS, Igor gets 4GB. On a 32-bit OS, it gets 2GB or 3GB if you tweak the OS. For details, execute this:
DisplayHelpTopic "Memory Management"


You should determine the size of the wave in bytes after loading it using the Data Browser.

If you are loading the wave as double-precision floating point, consider loading it as single-precision.

If you are truly limited by address space and there is no other solution, you can use the Windows 64-bit version of Igor. This should be used only by people who need to load gigabytes of data at one time. See the IGOR64 Read Me file.

January 7, 2011 at 06:56 pm - Permalink

Both computers are 32-bit.
XP Computer has 3GB memory, Vista has 2 GB.
The import function creates 4 waves of I16 each is 120 MBs. So a total of 480 MBs are imported.

January 10, 2011 at 10:16 am - Permalink

Quote:
Both computers are 32-bit.

This means they get a 2 GB virtual address space or 3 GB if you tweak the OS as described in the help under "Memory Management".

Quote:
XP Computer has 3GB memory, Vista has 2 GB.

I think you are referring to physical memory, not virtual memory. Regardless of how much or how little physical memory you have, a 32-bit application on 32-bit Windows gets a 2 GB virtual address space or 3 GB if you tweak the OS as described under "Memory Management".

Quote:
The import function creates 4 waves of I16 each is 120 MBs. So a total of 480 MBs are imported.

This isn't that much (your original post said "files 500 MB and larger") and I don't see why you would get out-of-memory.

There's not much you can do other than to configure the system to give applications 3 GB of VM as described in the help topic. Perhaps this was already done on your Vista system.

January 10, 2011 at 10:27 am - Permalink