Did you try setting up a new mission to see if the issue is still there?

Good Question. Yes I have. and other missions are still working, But,,, I have had other missions do the same thing. Also, I discovered in Arma 2 that if you placed something in the editor and then deleted it, it would still be documented in the mission file even though it was not on the map. I know this because I added a mod that a coop friend did not have so rather than him go get it, I deleted it from the map and he still could not play until I copied and pasted everything (less the unit I had deleted)into a new map and saved it and he could play. I mention this because I believe that your mission file retains units in it even though you have deleted them although I could be wrong. That being said, in a prior mission where the AI did not fire I had to delete and delete and then copy the remaining units into a new mission and save it to get the enemy AI to fire again. I would like to know if too many units is casing this. If you put too many Opfor, the preview button greys out and you cannot preview but if you place too many of a variety of units you can still preview but enemy AI stop firing. This understanding has come with a lot of testing and if correct, how many is too many and where can I get a running count? I have another mission where only about 1/2 the AI fire back and the others just walk around but never fire. It is frustrating to spend all that time building a mission that does not work.

I am having this same issue mostly after re spawning

Adding to your comment Patton18th. It happened to me to once after re spawning. AI were firing. we were in battle and were both killed. We re-spawned back at base and upon returning to the Area of engagement, the AI stopped firing.

Please attack a repro mission, zip up your folder and upload the ZIP here to the ticket.

O.K. I attached the file. When you start the mission tell the AI to hold fire. Then go out into the town and walk around. The AI do not fire at you.

Thanks, it's really intriguing, I can repro most of the time I start the mission.

If I had to take an educated guess, it looks to me like there are too many AI, which overloads the AI thread in a way, which prevents them to acquire you as enemy.

It would be interesting to know, how many groups of AI are the critical mass.

Well That was an original inquiry for me as well. How many are too many? To reiterate, I have placed so many on prior missions where the "Preview" button became unavailable until I deleted some units and it came back and I was able to preview. We really need some kind of way to compare the limit to the actual units placed to see if we are under the amount and our mission will in fact work.

Hi,
do you have this issue in actual version?
Thank you for more info.

I have had this issue as well, while playing the DUWS mod in single player. I also believe the issue is directly linked with the number of ai spawned, once there were too many units in one area everyone stopped shooting. After this had happened even killing off units would not fix the problem.

Out of curiosity, what was the AI amount on the map in the test mission causing the issue? Is the amount of AI arma can handle not dependend on the pc performance it runs on?

Hi,
repro mission of this size is almost impossible to debug,
I have FPS < 1 and there is lots of scripts and units (very hard to find the one I need)

Could you please remove everything non-essential so there is more straightforward repro.

Thank you.

This is fairly easy to reproduce with large unit counts and low FPS. On my system this bug occurs at an FPS of about 15, which is reached with about 600 units in an area.

I have added a simple repro mission, which dynamically adds enemy units with "Search and destroy" waypoint in an urban environment until the FPS drops to 15 (target FPS can be modified in "script.sqf"). There are also some friendlies units in the area as cannon fodder to encourage the enemy groups to switch to the more CPU expensive danger mode.

Repro steps:

1. Unzip and load attached mission "16709_AI_dont_fight.Stratis.zip" in mission editor. The mission will add enemy units around Agia Marina (shown on map with red circle marker).
2. Preview mission.
3. Player starts looking at a wall. Do not move or look around, just wait while the script automatically adds more and more enemy units unit the FPS drops below 15 (the logic for staring at the wall is a simple scene to render which means the FPS drop is solely due to AI related CPU load). Observe the hints and systemChat reports.
4. When script stops adding enemy groups, teleport to Agia Marina and see how enemy units react to your presence.
5. If AI react as expected, lower the _minFPS in script.sqf and repeat.

Couple of important (some obvious, but jic) notes regarding spawning of the AI:

AI receives a part of each frame's time - less FPS less time for any AI action.

AI takes some time to initialize and create all its "webs" - spawning AI rapidly should be avoided. Quick consequent spawning adds up to the initialization queue. (In the repro mission it can take several minutes before all the units create full awareness)

There is no fixed maximum of the AI units (and yes, excessive amounts cause serious issues) nor officially recommended (everyone has a different PC, some use the dedicated AI client and also PCs get better over time).

1. Mission designer should utilize any means possible to maintain reasonable frame-rate (several parts of the engine do not work ideally under low FPS conditions)
   1. By e.g. removing dead or unused units (and respawning them later), disabling various unnecessary AI properties, using only what matters, etc...

We could say to stick max. to around 100 active AI units (others disabled,...), but that is a very rough estimate and shouldn't be regarded as anything near any official recommendation ;)

Let me know if this is sufficient or you have any further questions. (about the mission AI management techniques please consult the forums, I won't be able to provide more detailed info about mission design here)

Otherwise, if it's sufficient, I'll close this issue. Thanks for the feedback & inquiry!