rtx 2080ti scaling

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stavros
Posts: 165
Joined: Tue Dec 02, 2014 1:29 am

rtx 2080ti scaling

Post by stavros »

hi.has anyone some data about 2080ti scaling for 1,x2,x4 sli 2080ti only for chess and Lc0? tnx
brianr
Posts: 536
Joined: Thu Mar 09, 2006 3:01 pm

Re: rtx 2080ti scaling

Post by brianr »

stavros wrote: Tue Feb 04, 2020 11:09 pm hi.has anyone some data about 2080ti scaling for 1,x2,x4 sli 2080ti only for chess and Lc0? tnx
I am far from an expert (and only have one 2080ti), but SLI does not help (and may slow down) Lc0.
For some benchmark info see:
https://lc0.org/benchmarks
crem
Posts: 177
Joined: Wed May 23, 2018 9:29 pm

Re: rtx 2080ti scaling

Post by crem »

brianr wrote: Tue Feb 04, 2020 11:39 pm
stavros wrote: Tue Feb 04, 2020 11:09 pm hi.has anyone some data about 2080ti scaling for 1,x2,x4 sli 2080ti only for chess and Lc0? tnx
I am far from an expert (and only have one 2080ti), but SLI does not help (and may slow down) Lc0.
For some benchmark info see:
https://lc0.org/benchmarks
Just to clarify, having multiple GPUs do help, it's just that they don't need to be connected with SLI.
jjoshua2
Posts: 99
Joined: Sat Mar 10, 2018 6:16 am

Re: rtx 2080ti scaling

Post by jjoshua2 »

The rule of thumb is that scaling is perfectly linear as expected adding cards, until you get to around 50k nps, and then going downhill to basically zero scaling once it hits 100k nps (2 to 4 thread CPU speed is what determines these numbers, IPC, boost, memory latency). Advertised max CPU boost speeds often aren't hit with 3 or 4 threads.

So how many cards depends on how fast each GPU gets and what size net you can do. For example a 10x128 might already be about maxed on a $300 RTX card and a 30x384 might not be maxxed on $32,000 4 x V100. And 6 to 8 GTX 1060s apparently scales quite well with most net sizes.
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Laskos
Posts: 10948
Joined: Wed Jul 26, 2006 10:21 pm
Full name: Kai Laskos

Re: rtx 2080ti scaling

Post by Laskos »

jjoshua2 wrote: Wed Feb 05, 2020 11:52 pm The rule of thumb is that scaling is perfectly linear as expected adding cards, until you get to around 50k nps, and then going downhill to basically zero scaling once it hits 100k nps (2 to 4 thread CPU speed is what determines these numbers, IPC, boost, memory latency). Advertised max CPU boost speeds often aren't hit with 3 or 4 threads.

So how many cards depends on how fast each GPU gets and what size net you can do. For example a 10x128 might already be about maxed on a $300 RTX card and a 30x384 might not be maxxed on $32,000 4 x V100. And 6 to 8 GTX 1060s apparently scales quite well with most net sizes.
You mean NPS scaling? How about strength scaling 1 -> 2 -> 4 -> 8 when the NPS is not maxed (say a large net on RTX 2060 GPU)? Wouldn't there be a larger and larger proportion of wasted nodes, even if NPS scales perfectly?