I have had programs that don't run correctly with Hyperthreading turned on. I asked NI about this and they say that they know LabVIEW doesn't work with Hypertheading!! For some reason they don't think it is important enough to mention on their web site. This is the message I got from NI:
Hello Bruce, Thank you for contacting National Instruments. The behavior you are seeing with relation to hyperthreading on the newest Pentium 4s is the expected behavior. LabVIEW (regardless of version) does not currently support hyperthreading. Until now, CPUs have had distinct threads even when multiprocessing, so an entire process always occurred on one 'processor'. Now, hyperthreading allows even one processor to 'pretend' like it is two, but the process can be shared between the two. We are currently working to determine whether LabVIEW can or should develop compatibilty in its execution structure to support the hyperthreading technology. Please let me know if there is any specific problems we might be able to help you with, that may not have to do with hyperthreading, or if there is any additional information you determine to be important. I hope this helps! Have a great day! Sincerely, Elizabeth Fausak Applications Engineer National Instruments
