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Multi-processor slow down

I am running an LV7 app that basically captures and processes data from 2 cameras simultaneously. It runs on a dual CPU machine with each grab and processing cycle in independant while loops. I've noticed that sometimes, for no apparent reason, one of the while loops will execute a lot slower than the other. In these instances LV (in general) uses less CPU time. I can think of nothing in the app that will cause this as quite literally it can run fine one execution and exhibit this problem the next with no change being made. I suspect there is a buffer building up or something like that as generally a PC reboot will fix this but everything is being managed correctly (or at least I think it is).

Anyone have any suggestions? I'm worried I may
be falling foul of some LV/Windows weirdness that I can do nothing about.

TIA
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Are you triggering the cameras, or simply acquiring from a fixed sampling rate.

The difference could be that both cameras are not running at 100% the same frequency. If one delivers pictures at 1Hz, and the other one at 1.05Hz, then after several captures, you'll notice a difference.

If you're triggering the cameras, then this shouldn't be the problem as your program is synchronising the two cameras.

I've had this "problem" with multiple parallel serial instruments. I ended switching to a queue-based producer-consumer model, and everything worked great.

Hope this helps.

Shane.
Using LV 6.1 and 8.2.1 on W2k (SP4) and WXP (SP2)
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Hi...

Yes the cameras are being triggered, but basically I have a separate vi generate the pulses on a timer card (can't remember which one off the top of my head). They are being triggered at separate rates but as you say it shouldn't matter too much as the program is triggering them.

I've experienced the problem again and found that by quitting out of LV and then re-openning my vi's it seems to sort itself out. I suspect it's a memory/resource allocation issue but I'm at a loss as to what.

Thanks for the reply.
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