Travis, on Mar 10 2008, 02:42 PM, said:
Here's something I thought I would throw out there. When I upgraded from 8.2.1 to 8.5, I found a wierd performance issue with 8.5 in one of my VIs. In 8.2.1 I had a VI where I used a case structure within two nested for loops that ran plenty fast; however, when I upgraded to 8.5 that same VI ran more than an order of magnitude slower. I coudn't find a good reason for it to happen. I tried recompiling and even tried making the VI from scratch again. The odd odd thing about this 8.5 performance issue is that it was a problem under both Windows and MacOS. I got around the issue by replacing the case structure with select node and drove on, but I made a note to go back and try to figure out what the deal was and never got around to it.
I'm just bringing this up because it seems possible that your implementation might make use of case structures within nested loops. The easy way to see if this is the issue would be to check the execution speed in 8.2.1. I would do it myself, but I don't have it installed anywhere anymore.
Travis
That's interesting. I don't think that this issue (you described) is what's affecting us. I just ran your test VI (test TCX read.vi) in LabVIEW 7.1 through 8.5 and here's what I get:
LVver, Whole, Divide and Conquer
LV8.5, 00:38, 00:30
LV8.2, 00:53, 00:46
LV8.0, 00:36, 00:28
LV7.1, 00:41, 00:33
As you can see, LabVIEW 8.2 performs the worst, but the other versions (7.1, 8.0, and 8.5) seem to be roughly equivalent.
I'm still looking at the code to see what we can do to improve the performance -- I'm confident that we'll find a good solution, soon. Certainly, there is room for improvement
-Jim