memory limits in LabVIEW on Windows XP

[Alan Hahn]

Is there some limit to an array size in LabVIEW on a Windows XP system?

I am aware of memory copies etc, and try to avoid them, but I was under the (perhaps mistaken) impression that a program would try to grow its memory until some physical limit (like the amount of VM available). I just added 2Gb of ram to this machine, but see that an array ~200-500Mb range causes  LV 8.5 to give up with a memory full error---I am sure it isn't even touching VM yet. When I use the windows Task Manager, it certainly seems to still have memory available when LV halts. Before I put the memory in, smaller arrays would bounce me into VM, slowing things down tremendously, so I thought adding more physical memory would allow me to grow the array larger.

I see other similar questions, but no one seems to answer (or know the answer to) the basic question of a maximum memory size? In other words, yes there is or no there isn't.

Thanks, and sorry if I sound like a PITA, but this seems a little strange to me. I have been using LV since the 2.0 days and have always fought memory issues with large arrays (back in those days with cpu's with ~8Mb memory and Mac 7.0 fixed program sizes!), but I had thought those days were behind us--at least compared to modern machines and massive memories and harddrives.

[altenbach]

Some light reading for the weekend 😄

How Much Memory Can LabVIEW Use?

Managing Large Data Sets in LabVIEW

One quote from the above article that might apply to your case:

"... Now that you know how to create large data sets, how much memory can you expect to allocate? The answer depends on several factors. When LabVIEW allocates an array, it requests a contiguous memory section. If your memory is fragmented, you may get an out-of-memory error even though you still have hundreds of megabytes of free memory. You can work around this somewhat by allocating your data in chunks...."

[Alan Hahn]

Thanks,
That may explain what I am seeing. At least now I won't beat my head against the wall trying to fight what may be a system "feature".
Alan