TLDR, even when compared to equal vanilla render distances, LOD rendering causes a significant FPS hit, and I would like to understand why/if there is anything I can do to mitigate it.
Hi! I'm trying to tune things for my players and can't seem to wrap my head around the performance hit I take whenever LOD rendering is enabled. For example at vanilla render distance 32, LOD rendering disabled I get ~100 FPS, but at vanilla render distance 8, LOD render distance 32, I get ~40 FPS. I have tried the above test on both the latest release (2.2.1) and after compiling an up to date version of 2.3.0. I know such short radii aren't really the target use case, but I have observed the same effect for all combinations of vanilla render distance, up to 45, no matter what my DH settings are, even with short LOD radii and the quality set to "chunks".
Some other possibly useful info: The only other mod installed is ModMenu. All tests were done while connected to a dedicated server on separate hardware. Enabling DH maxes out my graphics usage at any setting (integrated graphics), although it's at at least 50% even with LOD rendering disabled. My CPU usage varies from 25%-50% depending on my CPU load setting (minimal<->I paid for the whole CPU). The framerate reduction is the same for tiny ranges at chunk quality, and high ranges at block quality. For tests with 2.3.0, I also included DH serverside and waited to receive all the generated chunks. 6gb of RAM is allocated to MC. I have tried the usual suite of optimization mods, with similar results....
Solution:DH does a constant base reduction in fps, does barely decreases with bigger RD at least on medium quality