Crash: signal 11 (SIGSEGV), code 1 (SEGV_MAPERR)

I have an Oculus Go app that is crashing for people with disturbing frequency. Some users know how to adb logcat, and what they send me looks like this.

So it seems like it's running out of GPU memory, I guess? But I'm not certain I'm interpreting it correctly. Nor do I see why that causes a crash rather than something like pink materials.

Any tips on how to narrow this down, and what I can do about it?

 

In case it's useful, here's the result of

adb shell dumpsys meminfo

on my device after playing a while. (I did not experience a crash, however.)

Code (csharp):

1. Applications Memory Usage (in Kilobytes):
2. Uptime: 739145165 Realtime: 925678597
3.  
4. ** MEMINFO in pid 28970 [com.alvios.quivr] **
5.                    Pss  Private  Private  SwapPss     Heap     Heap     Heap
6.                  Total    Dirty    Clean    Dirty     Size    Alloc     Free
7.                 ------   ------   ------   ------   ------   ------   ------
8.   Native Heap   602902   602772        0        0   642560   621237    21322
9.   Dalvik Heap     4577     4156        0        0     9933     5960     3973
10. Dalvik Other      711      708        0        0                          
11.         Stack     1004     1004        0        0                          
12.        Ashmem       16        4        0        0                          
13.       Gfx dev   470520   409952        0        0                          
14.     Other dev        8        0        8        0                          
15.      .so mmap    16584      500    14060        0                          
16.     .jar mmap        4        0        4        0                          
17.     .apk mmap     7700      340     3368        0                          
18.     .dex mmap     2197       12     1920        0                          
19.     .oat mmap     4954        0     2352        0                          
20.     .art mmap     3388     1568      588        0                          
21.    Other mmap       68        4       28        0                          
22.    EGL mtrack    29600    29600        0        0                          
23.       Unknown    25326    25312        0        0                          
24.         TOTAL  1169559  1075932    22328        0   652493   627197    25295
25. App Summary
26.                        Pss(KB)
27.                         ------
28.            Java Heap:     6312
29.          Native Heap:   602772
30.                 Code:    22556
31.                Stack:     1004
32.             Graphics:   439552
33.        Private Other:    26064
34.               System:    71299
35.                TOTAL:  1169559       TOTAL SWAP PSS:        0
36. Objects
37.                Views:        6         ViewRootImpl:        1
38.          AppContexts:        2           Activities:        1
39.               Assets:        3        AssetManagers:        2
40.        Local Binders:       29        Proxy Binders:       26
41.        Parcel memory:       15         Parcel count:       60
42.     Death Recipients:        2      OpenSSL Sockets:        2
43.             WebViews:        0
44.  

 

No ideas?

What about some way to measure how much GPU memory is in use (ideally, as a percentage of total), at runtime, so I can see whether my efforts at optimization are having any effect?

(I did go through with Resource Checker and reduce all my texture sizes; most of them are 1k by 1k now. But the crash is still occurring.)