BUG: iOS app asserts in background when it goes to sleep

Hey Guys,

I’ve noticed that if our iOS app goes to sleep naturally, after 10 seconds of being asleep the app asserts in the background and gets killed.

This specific log snippet is of interest:

Feb  3 16:58:23 Iphone-6-plus assertiond[67] <Warning>: <BKNewProcess: 0x1476224e0; com.uppercut-games.dodgers; pid: 1268; hostpid: -1> has active assertions beyond permitted time: 
	{(
	    <BKProcessAssertion: 0x14752c2b0> id: 58-D3C98E1F-9764-48B1-A166-2BCBBAB83CFD name: Deliver Message process: <BKNewProcess: 0x1476224e0; com.uppercut-games.dodgers; pid: 1268; hostpid: -1> permittedBackgroundDuration: 10.000000 reason: suspend owner pid:58 preventSuspend  preventThrottleDownCPU  preventThrottleDownUI  preventSuspendOnSleep ,
	    <BKProcessAssertion: 0x147522ab0> id: 58-A6DF586F-4DF9-43A4-90E6-B29DA1F0B878 name: Suspending process: <BKNewProcess: 0x1476224e0; com.uppercut-games.dodgers; pid: 1268; hostpid: -1> permittedBackgroundDuration: 10.000000 reason: suspend owner pid:58 preventSuspend  preventThrottleDownCPU  preventThrottleDownUI  preventSuspendOnSleep 
	)}

I’ve attached the full log after the app goes to sleep [HERE][1].

I’ve tested this in a blank template project using the launcher engine version of 4.10.2.

I have managed to repro this on 8.x and 9.x versions of iOS, so this isn’t version specific either.

Any solution for this would be awesome.

Let me know if you need anymore info.

Cheers.

77083-sleepcrash.txt (4.86 KB)

This is most likely the same bug I just fixed which is the frame limiter not properly working when the device goes to the lock screen. I have put a fix in 4.11, but I am not sure if it made it into Preview 4. For the time being, you can go to your games IOS project settings and set the frame rate to None and that will disable the limiter.

-Pete

Yep, this is the same issue. Uncapping the framerate did stop this from happening.

Would it be possible to link to a Github changelist with the fix, or possibly a code snippet?

We’d like to merge it into our current version of the engine.

Cheers.

You should be able to get that information from here: https://github.com/EpicGames/UnrealEngine/commit/52d692c821e8cdf65b2a2b2e25a422b1234c94f1