What is the deal with Terrain Level of Detail (TLOD)?

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TLOD is a CPU limiter, as is OLOD, so there are two scenarios where your CPU gets limited

  1. CPU loaders being too high. CPU loaders are: TLOD, OLOD, TRAFFIC (of all types, including airport traffic and workers etc), and clouds.

  2. CPU can also become limited if your GPU isn’t working hard enough. This is often seen when you have higher end GPU’s with low loads eg running a RTX30x series at 1440p or 1080p instead of 4K. It creates a situation where the GPU under light loads will be ‘twiddling its thumbs’ while continually asking the CPU for more data and the CPU can’t cope. The way out of this situation (counter intuitively) is to load the GPU more. So main drivers of GPU are most other graphical sliders (except LOD’s and clouds), and more significantly: output res and render scale.
    Quite often people can achieve a less CPU limited situation by keeping their GPU’s busier.

So to get back to your original ? TLOD can be increased if you are not CPU limited. If you have a good GPU then load it more to stay out of CPU limited situations and this may allow higher LOD’s.

Having said that, the max TLOD I use is 200 on a 5950 with 3090 GPU while locking my FPS at 30FPS/60Hz (VSYNC). Works well for me usually. I don’t believe the people with TLOD of 400 have great performance, they must be flying GA only with no AI traffic or weather. Or just tolerate CPU limited stuttering. The TLOD slider could actually be renamed to ‘CPU mainthread limiter’ and ‘400’ could be labelled ‘max’.

Interestingly if you run out to buy a RTX40x series card, there is probably just as big a chance of staying CPU limited (with stutters) with this sim, unless of course you load/balance it correctly.

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