Hey ndo,
After speaking with an engineer from R&D, I believe I have some relevant information to pass along.
1) RTJunk.vi appears to be a benchmarking VI. While this is a very good start, we do offer a benchmarking VI that ships with LabVIEW, and provides an easy way to benchmark your code. You can find this project file by opening LabVIEW, and going to Help >> Find Examples. Once you are in the NI Example Finder, select the Toolkits and Modules >> Real Time >> Benchmarking folder. You can place your code in that VI, and get benchmarks from that.
2) Try changing the Process Data VI from a sub routine to a Time Critical VI. That could increase your performace.
3) Your Process Data VI could use some memory improvement. Currently every time you call the VI, you are having to allocate new memory for the arrays you are using. First, I would suggest passing the input array into the Process Data VI. Second, I would recommend that instead of using Array Subset VI, I would first use Initialize Array to create the memory space, then use Replace Array Subset to put that data into that Array. I have included a picture below of an example of how to preallocate array memory, and fill it using the Replace Array Subset.
Some other points about Memory Management:
- The LabVIEW Real-Time Module memory manager is a shared resource
- It is recommended that all memory allocations be removed from a time-critical loop
- It is a good idea to preallocate arrays outside of the time-critical loop
Also, many of these topics are covered in our LabVIEW Real Time Customer Education class. If you are interested in learning more about that, I can get you that information as well.
Regards,
Kevin H
Message Edited by Kevin_H on
01-16-2008 03:43 PM
National Instruments
WSN/Wireless DAQ Product Support Engineer
