Where do auxiliary apps like Radar Contact, FS2Crew, ASA 2012, as several examples, get placed into the virtual memory when running simultaneously with FSX?

 

Does Radar Contact, or FS2Crew,or ASA 2012 run in their own 4GB virtual memory spaces, or all together in a 4GB virtual space separate from FSX, or run in the same 4GB maximum memory space with FSX?

 

With all the add-ons out in the market that can potentially run at the same time, is there a way you can force them to run in another virtual memory space to eliminate a potential Out of Memory (OOM) situation with FSX?

 

This is a topic I have yet to see any information about as to what is actually happening.

 

Bill Clark

The reason you aren’t seeing much info about it is that it’s a scary subject.

 

Add-on developers write their masterpiece without taking into account what the others are doing.

 

Despite new machines selling with 8, 16 GB of RAM, FSX is still a 32 Bit application, and the 4 GB limit you mentioned acts like the sound barrier for an aircraft. Go near that at your own risk. =@

 

I can’t speak for other applications, (OK will just say that I know RC4 runs in its own 4GB address space), but I will mention this...

 

We develop a voice control application for FSX & FS9.

 

In early days (2004) we had to decide whether to run our entire application inside the FS9 process (FSX wasn’t around then). It looked cool, and at the time very few add-ons would saturate the sim memory wise.

 

After observing the speech engine behaviour over a couple of years, we decided it was too risky to do that. I mean who wants to see a long haul flight going CTD as a result of the speech engine leaking memory or our virtual co-pilot having one of those moments. :Drooling:

 

In the end we found the better approach is to load a dll in the FS process. The latter will run the absolute minimum code to interact with the sim (we’re talking less than 10 MB), while the heavy and risky part (about 200 MB for speech engine (possibly far more) and a very large voice file (200 MB)) would run outside it.

 

That way, our app would hardly if ever compromise the integrity of the flight, which is the most important thing. It can of course crash (even if it’s extremely rare these days after 8 years development), but it won’t take the sim down with it. You would just need to restart it (takes 15 seconds).

 

When we took that decision a while ago we didn’t really foresee the advent of all these memory hungry add-ons coming out these days. Some, like aircraft and scenery add-ons have no choice but to run inside the sim, so these should have some priority but at the same time must exercise some restraint.

 

With our approach we leave the fight for resources to others.

 

And to answer your other question, there is no way to force an add-on designed to run inside the sim process to run outside it. If someone can manage it one day, that would be news to me.

And to answer your other question, there is no way to force an add-on designed to run inside the sim process to run outside it. If someone can manage it one day, that would be news to me.

What about GSX ? Runs from the couati engine which runs outside of FSX. That's how I understood it from reading Umberto's explanation.

What about GSX ? Runs from the couati engine which runs outside of FSX. That's how I understood it from reading Umberto's explanation.

 

Just to clarify, what I meant by that, there is no way for a user to say right-click on add-on exe and tell it to run as a separate process.

 

You can of course start another process from the sim, if you already have a dll running inside it. Or have the external process run automatically when you start the sim by adding an entry to “exe.xml”

 

Needless to say Umberto would be the best person to speak about GSX.

 

It’s a good thing that “couatl.exe” lives outside the sim though.

 

That way part of the program can run outside, and only things to do with scenery (bgl data and object models which cannot run outside) will need to grab some resources from the virtual address space. GSX vehicles will need a little bit of that. But these resources are reclaimed as soon as the vehicles go away.