Lc0 settings for Leela on GPU- Nvidia RTX 2080

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sincerelybrent
Posts: 47
Joined: Fri Feb 15, 2019 11:41 pm
Full name: Brent M

Re: Lc0 settings for Leela on GPU- Nvidia RTX 2080

Post by sincerelybrent »

Consider changing your CPUCT value for different time controls. 3.4 is good for bullet chess. 2.0 is good for TCEC controls (120’/40).

If you have “only” one video card, set threads to 2. More doesn’t help.
ankan
Posts: 77
Joined: Sun Apr 21, 2013 3:29 pm
Full name: Ankan Banerjee

Re: Lc0 settings for Leela on GPU- Nvidia RTX 2080

Post by ankan »

I agree that 2 threads is optimal for single GPU, and you must have --backend=cudnn-fp16 (to get ~2.5X speedup over the default cudnn fp32 backend).
Changing some of the settings for more NPS can weaken the search. E.g, I wouldn't suggest increasing minibatch-size more than the default (256).
Increasing NNCache setting is pretty safe though (i.e, increases NPS without changing the search). I normally set it to 10million and leave all other settings to defaults. People have found some small improvements with non-default CPUCT settings, but I haven't personally tested them.