Set 1
Mesh res.=32
Tile mipmap policy=All levels
Max. res. level=21
I did six tests and it works without problems. First I tried the same scenario three times, and ~1.4 Gb of Video RAM was used. But hen I tried the same scenario running it as "Current State" on Launchpad and ~2.2-2.5 Gb of Video RAM was used (all these last three times). No texture problems and no crashes. See 32.log. I couldn't reproduce that one case I mentioned above.
Set 2
Mesh res.=64
Tile mipmap policy=All levels
Max. res. level=21
It's almost immediately causes texture problems, crashes and freeze every time. I did five tests (with the same scenario and my actions). Sometimes Orbiter crashes after a few seconds after the ship accelerates. Also, I noticed that sometimes I can't make screenshots with Prt Sc key on keyboard and insert it to Paint, so I had to open some other window like Logitech Profiler to make a screenshot). Here are screens of tests 1, 2, 5 and log files of tests 1-5.
Set 3
Mesh res.=64
Tile mipmap policy=Low level only
Max. res. level=21
The same textrue artifacts (even crazier (look at the sky) and crashes:
Set 4
Mesh res.=64
Tile mipmap policy=All levels
Max. res. level=19
The same texture problems.
Set 5: Orbiter 2016 with Mesh res.=64
It works without problem.
Set 6: OpenOrbiter build from 6 Jun 2023 with Mesh res.=64
It also works fine.
So, it seems to be caused only by 64 mesh resolution in the latest builds. Sadly I haven't a previous Orbiter build where 20-21 levels were added, but MIP Maps for all levels not yet. Maybe it makes sence to try it with 64 mesh resolution. I just deleted that build and don't know where to find it now.
Added: Oh, I'm very sorry, here:
Once I've get the texture problem (as on the picture above) even with a 16 value, but without a crash.
Here are my 16 and 32 causes:
And once the following happened. I run a scenario (with a 16 value), flew for a while, and noticed that ~2.4 Gb of my Video Memory is used. Then I completely closed Orbiter, opened it again, run the same scenario, flew for the same time in the same area, and noticed that only ~1.4 Gb of my Video Memory is used (I monitored it with MSI Afterburner). And I haven't run other applications.
I made a mistake. Here are my 32 (not 16) and 64 (not 32) cases. And once I've get the texture problem even with a 32 value (NOT 16), but without a crash. But now I couldn't reproduce texture problems/crashes with 32 mesh resolution. Maybe this happens very rarely or I was wrong with that one case. I hope more tests will be done by other users.