type of preemptive scheduling

[Peron]

I am new in Labview real time. I've seen that Labview real time scheduler combines round-robin and preemptive scheduling. If possible, I would like to know which kind of preemptive scheduling applies, that is (as far as I know) simple priority inherence, priority ceiling or immediate priority ceiling. I have been searching this information and the only thing clear is that a higher priority thread that needs to execute suspends execution of all lower priority threads.

Thank you so much.

Bayonas

[Diego_M]

Hi Bayonas,

in the following link you can find an explanation reference to your question:

http://forums.ni.com/ni/board/message?board.id=170&message.id=62696&requireLogin=False

More info:

http://zone.ni.com/devzone/conceptd.nsf/webmain/5033f0053858154d8625 and you can find a tutorial about Multitreading in the following link

http://zone.ni.com/devzone/conceptd.nsf/webmain/d2e196c7416f373a862568690074c759

I hope this helps you.

Regards

Diego M.

[Peron]

Thank you for your reply. Although it was not exactly I was asking for, the linked documentation has responded to many other questions I had. As my question is concerned, I think I found the answer in the white paper Phar Lap ETS™ - An Industrial-Strength RTOS  in http://www.ardence.com/embedded/products.aspx?ID=295. This document provides information about Phar Lap OS features (it is necessary to be registered in order to get the document. Anyway, if someone is interested in it, I can send it by mail). It seems to be that the priority inversion is avoided by simple priority inheritance.

After reading your linked documentation, some questions have arised within my head:

-each prioritized execution system has its own queue and two threads devoted to handling block diagrams on that queue. Is the second thread only used to manage synchronous/ blocking nodes?

-Is it possible to use fixed point representation inLabview instead of floating point?

Thank you in advanced.

Regards,

Bayonas