CriticalSection in the Synthesizer class

[eyalamir]

Yes, I agree. I think those locks should probably be replaced by SpinLocks or removed entirely.

Having that said @fr810 recently posted that that might not be an actual problematic issue:

Mutex in the processBlock?

I’d just like to add that all modern OSes use double lock checking for general purpose mutexes (for example JUCE’s CriticalSection), i.e. they first check if a lock is held with a cheap atomic memory operation. Only if it is contended do they need to call an expensive system call. This means that a lock that is never contended is perfectly ok to use in realtime code. Obviously, a lock that is never contended is a bit useless, but we often need to use locks to guard against exceptional behaviour…