I believe that the release version of MFS has performance issues in its SimConnect code. 3rd party applications which use SimConnect and worked fine with the alpha and beta releases of MFS now produce stutters in the release version.

I also believe that the software running our yoke is either buggy or reckless and produces an incredible amount of SimConnect requests. Last year, I used FSUIPC to log the SimConnect events by CLS2Sim. After just 10 minutes of logging, FSUIPC created a logfile with 600,000 lines of output. I am not sure how many lines of output each SimConnect request results in, but it might well be that CLS2Sim (in the version that I tested) produced up to a 1000 SimConnect requests PER SECOND.

Now combine those two observations and it seems very possible that once CLS2Sim connects to MFS, the sim will spend almost all of it’s time processing SimConnect events… thus it hangs.

One could argue that Asobo “just needs to fix” the performance issues, but one might also say that perhaps Brunner could do its part as well to reduce the load on SimConnect by checking their code for the reason of the very high amount of SimConnect requests.

I did not inspect CLS2Sim’s behaviour for fun, but because I had other issues, which were, in my opinion, caused by overwhelming SimConnect on my machine.

Caveat: I have not used the alpha or beta versions of MFS myself. I have not used my yoke for months (out of frustration with certain issues). I’m back to flying with my Warthog, even though it doesn’t provide the kind of immersion the yoke might provide.

Perhaps someone who’s a bit tech-savvy can look into this, check whether the number of SimConnect requests from CLS2Sim is still as high as it was when I looked at it. Not sure if FSUIPC7 can log SimConnect events yet, but I guess you could just use your P3D install, the behaviour of CLS2Sim is probably the same.

If you can verify the “up to a thousand SimConnect events per minute”, you might ask Brunner about it. I think I have lost the goodwill of the Brunner support people. I raised this issue with Brunner support in October 2019 and never received a response.


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