PrepareMeshRenderNodes > CalculateLODFade crash

Finally hit this crash that I've been seeing reported via Xcode crashes for months on my own device, and this is what it looks like:


Before it happens, the screen hangs for a while and I get a bunch of spam in the console that ends with this:

Code (CSharp):

1. (Filename: ./Runtime/Allocator/ThreadsafeLinearAllocator.cpp Line: 313)
2.  
3. Internal: deleting an allocation that is older than its permitted lifetime of 4 frames (age = 5)
4. (Filename: ./Runtime/Allocator/ThreadsafeLinearAllocator.cpp Line: 313)
5.  
6. Internal: deleting an allocation that is older than its permitted lifetime of 4 frames (age = 5)
7. (Filename: ./Runtime/Allocator/ThreadsafeLinearAllocator.cpp Line: 313)
8.  
9. Internal: deleting an allocation that is older than its permitted lifetime of 4 frames (age = 5)
10. (Filename: ./Runtime/Allocator/ThreadsafeLinearAllocator.cpp Line: 313)
11.  
12. Internal: deleting an allocation that is older than its permitted lifetime of 4 frames (age = 5)
13. (Filename: ./Runtime/Allocator/ThreadsafeLinearAllocator.cpp Line: 313)
14.  
15. 2020-01-12 03:30:43.874562+0300 gamename[8835:202554] TIC Read Status [12:0x2838649c0]: 1:57
16. 2020-01-12 03:30:43.875398+0300 gamename[8835:202554] TIC Read Status [12:0x2838649c0]: 1:57
17. 2020-01-12 03:30:43.875784+0300 gamename[8835:202554] TIC Read Status [12:0x2838649c0]: 1:57
18. 2020-01-12 03:30:43.882051+0300 gamename[8835:202554] [BoringSSL] nw_protocol_boringssl_get_output_frames(1301) [C12.1:2][0x1243814a0] get output frames failed, state 8196
19. 2020-01-12 03:30:43.882680+0300 gamename[8835:202554] [BoringSSL] nw_protocol_boringssl_get_output_frames(1301) [C12.1:2][0x1243814a0] get output frames failed, state 8196
20. 2020-01-12 03:30:43.884900+0300 gamename[8835:202554] TIC Read Status [12:0x0]: 1:57
21. 2020-01-12 03:30:43.885530+0300 gamename[8835:202554] TIC Read Status [12:0x0]: 1:57
22. 2020-01-12 03:30:43.885803+0300 gamename[8835:202554] TIC Read Status [12:0x0]: 1:57
23. 2020-01-12 03:30:43.886095+0300 gamename[8835:202554] TIC Read Status [12:0x0]: 1:57

with the "deleting an allocation" mentioned thousands of times before that similarly.

So far I haven't been able to cause this reliably (kind of happening randomly mid-gameplay), and I'm pretty sure I wouldn't be able to provide a repro project on this. This doesn't happen in editor or on Android so far.

Using Unity 2019.2.16, crash happened on iPhone 6s, but it seems to be pretty device agnostic:


Any ideas as to where to start digging into this?

 

Since this crash is obviously LOD related, I've tried drastically reducing the amount of the most taxing LODGroups in my scene (trees in my case) and the issue lessens or disappears. I'll see if I can't build a repro scene based on this

 

Hey @aVolnov we have crashdumps showing the same callstack on Windows.
Did you manage to resolve this issue?