MixThreadCount = ?

Greg:
I believe if the use multiprocessor is enabled in Options/Audio, the MixThreadCount in the Aud.ini file goes automaticlly to the "1" condition (0=off, 1=on).
Please, anyone correct me if I´m wrong.

Hudson:
Thank you for clarifying this. I did believe this setting was as the normal 0/1 Windows rule (off/on). Sorry if I posted an incorrect help.

Hudson:
You´re a gentelman.
Thank you.

This is even more of a reason why I would REALLY, REALLY like to know what the variables in the aud.ini file do! I know you can't or don't want to tell us what all of them do, but please let us know about the really important ones so we can know that they are truly getting set to the correct values.

For example, "Use24BitExtensible". What does this variable do? Mine is set to "0". I have "Audio Driver Bit Depth" set to 24 in the audio dialog box, along with the default "File Bit Depth". If this variable is set to 0, does this mean I'm not really getting 24 bit depth somewhere in the program? Maybe Sonar is reading my Delta 66's as not supporting 24 bit?

Apparently "EnableMixThreads" is the variable that gets set to either 0 (false) or 1 (true) when you check or uncheck "enable multiprocessor". HOWEVER, when I do enable it, MixThreadCount stays at 0. Like I said in the first post, with it enabled I got glitches and dropouts. When I manually changed MixThreadCount to 1 and enabled the multiprocessor engine, finally, the glitches and dropouts went away. My cpu usage also seems to have gone down a bit (though I know not as much as if I had 2 real processors).

When MixThreadCount is set to zero, SONAR will allocate one thread per CPU. By setting it to 1, you are overriding this behavior and forcing SONAR to use a single thread even though you have multiple CPUs.

Your glitches and dropouts due to enabling MP may be caused by your driver or some plugin not being fully MP capable. Some plugins seem to keep "global" data that is assumed by the plugin code to be accessed by one thread at a time. This isn't true when SONAR 3.1 MP is enabled.

Really? accord to Noel it is extra threads ..

"Use Multiprocessor Engine" MixThreadCount Total Engine threads
==================================================
1. OFF 0 (ignored) 1 (default thread)
2. ON 0 Number of CPU's
3. ON n (>0) n+1

The MixThreadCount when greater than zero really specifies the number of EXTRA worker threads to be created. We always have (and have had since Pro Audio) one available audio engine thread. So setting it to a value of 2 explicitly ends up creating 3 threads in all, one original thread and two extra worker threads. You are free to experiment with these values, but please note that using more (total) threads than the number of CPU's may actually result in worse performance, due to the context switching overhead and the threads competing with themselves. For most practical purposes leaving MixThreadCount at its default value of zero will yield the best performance. If, however, you find empirical results that indicate you are getting better performance with a higher count let us know.

Sorry for the confusion.