Support more parallel instances in the parallel FOR loop

[altenbach]

The number of parallel Instance is currently capped at 64, independent of hardware. This limit should be raised.

First Reason: Since even 64 bit Windows 7 supports up to 256 cores, it would be reasonable to raise that limit to 256.

(Even the next version of windows mobile (8) will support 64 cores. (Mobile! On a Phone! 🐵. Obviously the upcoming hardware is fast moving in that direction.)

Second Rason: Sometimes it is useful to generate many instances, even if we have fewer cores available, for example maintain individual data in a large number of identical reentrant subVIs. (Such an usage example where we want many instances even on a single core machine can be found here)

Idea: Raise the max number of parallel Instances of a parallel FOR loop to 256.

[PaulG.]

Why stop there?  Raise this number with each major revision to match current technology.

[mfletcher]

We put a cap on the number of instances because LabVIEW can run out of memory when generating higher numbers of instances, especially when you have nested Parallel For Loops. We may consider raising the limit though.

For now, you can change the limit in your config file.

ParallelLoop.MaxNumLoopInstances=256

[altenbach]

>For now, you can change the limit in your config file.

Thanks! I guess that will do, even though we don't actually have hardware to support it yet. 😉

[wiebe@CARYA]

On a related note:

https://forums.ni.com/t5/LabVIEW/How-does-it-iteration-parallelism-works/m-p/3750914/highlight/false...