Client crashes on iOS when I try to catch hitches


  1. Start client for iOS.
  2. Typing commands in console:
  • stat unit
  • t.HitchThreshold 0.5
  • stat hitches
  • stat dumphitches


Client crashes after typing command “stat dumphitches”.

Crash was reproduced on iPad mini 4, iPad Air 2 and iPhone 5.

When I reproduce these steps on Android devices, there are no crashes happens, info about hitches succesfully writes to log.

Today we updated our project to UE 4.11.1 but problem was successfully reproduced.

4.11.1 don’t fix it.

Hi lepis,

I am not sure what you mean by the first repro step “Start client for iOS…” Are you referring to Mobile Preview (PIE)?


I ment our game developed on UE4.

I start game, input these commands and application crashes after inputing 4th command.

The same application doesn’t crash on Android.

I am unable to reproduce the issue following these repro steps:

  1. Open game “Tappy Chicken” in UE4.11.1

  2. Set to Play>Mobile Preview (PIE)

  3. In Editor Preferences>Play>Play in Standalone Game>Common Window Sizes: select “Apple iPhone 5, 5s, iTouch 5 (Portrait)”

  4. Play

  5. Press " ~ " to bring up Console Commands

  6. Execute each of the following Console Commands one at a time:

                                  stat unit
                                   t.HitchThreshold 0.5
                                   stat hitches
                                   stat dumphitches

RESULT: No Crashes

If this is not the way you are testing, please list (Step by Step) how you are testing your project.

We are starting our UE application on real devices, without emulators and UE player.

Anyway, I repeated your steps in UE player, but our app wasn’t crashed. Like on Android.
It crashes only on iOS devices.


  1. I’m building our project: UE dedicated server, iOS client, Android client.

  2. Installing clients on iOS and Android devices.

  3. Starting applications.

  4. Typing 4 commands into console.


Android application work correctly.

iOS application crashes.

Thanks for the update. I was not able to reproduce this by typing the console commands in the Tappy Chicken project after being deployed to an Apple iPad, packaged for development.

In order to help isolate the cause of your crash, please provide the following logs:

  1. If the Crash Reporter window is present when the crash occurs, select “Copy Callstack to the Clipboard,” and paste that information in a document and add to this post. Be sure to hit “Submit” on the Crash Reporter pop-up to send the Crash Report to Epic.
  2. The UE4.log (Located: ~/Library/Logs/Unreal Engine/Editor/)
  3. The ProjectName.log (Located: ~/Library/Logs/Unreal Engine/ProjectNameEditor/)


I made logs from iOS device — crash log.

Application crashes after typing command stat dumphitches. It’s unnecessary to type 3 first commands.

I remind that crashes only on iOS. On Android and UEPlayer it works correctly.

Can you attach with Xcode before making it crash? We need an actual callstack to be able to identify the source of the crash.


I attached logs + links to screenshots at the end of the letter. Is it what you need? If not, could you write me steps to get right info from Xcode? I’m just a tester and don’t have a lot of experience with XCode.

From the attached logs, looks like a stack overflow is a good possibility.

In .cpp, around line 955:

void Start()
	FRunnableThread* Thread = FRunnableThread::Create(this, TEXT("StatsThread"), 512 * 1024, TPri_BelowNormal, FPlatformAffinity::GetStatsThreadMask());
	check(Thread != NULL);

Change the *512 1024 part to 2048 * 1024 and see if it works better

If that does not correct the issue, here is a link describing how to attach with XCode to a running process:

Hi lepis,

Since we have not heard back from you in a few days, we are marking this post “resolved” for tracking purposes. However, if you are still experiencing crashes after typing the console command stat dumphitches on your iOS device, please follow the steps for attaching with XCode (link above) and post your results.


Sorry me for not answering for long time. I had no possibility to rebuild engine. Now I did it.
I works stable with changes in .cpp.

Thank you very much for your help.