How good is the RTX 2080 Ti for Leela?

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Milos
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Re: How good is the RTX 2080 Ti for Leela?

Post by Milos » Fri Sep 21, 2018 11:39 am

jkiliani wrote:
Fri Sep 21, 2018 6:27 am
Lion wrote:
Fri Sep 21, 2018 6:15 am
Thank you !

Can you or someone else explain me what is fp32 and fp16 and how to set that?
Is that also existing with other GPU such as the 1080Ti and or 1060 ?

rgds
Small update, Ankan added the 2080 to his benchmarks:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000

             fp32    fp16    
Titan V:     13295   29379
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472
About fp32 and fp16, this is the calculation precision of the neural network inference. fp32 refers to 32 bit floats, fp16 to 16 bit floats. It has been experimentally confirmed that the reduced floating point accuracy of 16 bit NN inference does not reduce playing strength for Lc0 significantly. However, there is not much point with GTX 10xx GPUs since those are not optimised for fp16. The RTX cards on the other hand are, in their case fp16 gains a large amount of speed as can be seen from those benchmarks.

As for how to use, it, you initialise Lc0 with "backend=cudnn-fp16" instead of "backend=cudnn".
So Titan V benefits the least, then 2080Ti than 2080 benefiting the most from tensor cores, almost 70% additionally to fp32 performance. Interesting.
Still even with 2080 Tensor cores are using only 10% of its maximum bendwidth. With Titan V that was less then 5%.

Milos
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Joined: Wed Nov 25, 2009 12:47 am

Re: How good is the RTX 2080 Ti for Leela?

Post by Milos » Fri Sep 21, 2018 11:44 am

jkiliani wrote:
Fri Sep 21, 2018 10:14 am
Robert Pope wrote:
Thu Sep 20, 2018 8:29 pm
How does that compare to a 1080 or 1080 ti?

Code: Select all

             fp32    fp16    
GTX 1080Ti:   8996     -
Titan V:     13295   29379
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472 
So an RTX 2080 will give around a factor 3 improvement to the GTX 1080 Ti when using fp16 which the GTX doesn't support. For the 2080Ti, the improvement is a factor of 3.6. The RTX 2070 isn't released yet, but I would guess it should still pull around 20k nps on fp16, for a much lower power consumption and purchase price than the 1080Ti.
Considering how small Tensor cores impact on performance is 2070 will definitively be best bang for the buck.
Plus 2x2070 should be 25% stronger than 2080Ti at the same price and power consumption practically.

Lion
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Location: Switzerland

Re: How good is the RTX 2080 Ti for Leela?

Post by Lion » Wed Sep 26, 2018 12:38 pm

jkiliani wrote:
Fri Sep 21, 2018 6:27 am
Lion wrote:
Fri Sep 21, 2018 6:15 am
Thank you !

Can you or someone else explain me what is fp32 and fp16 and how to set that?
Is that also existing with other GPU such as the 1080Ti and or 1060 ?

rgds
Small update, Ankan added the 2080 to his benchmarks:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000

             fp32    fp16    
Titan V:     13295   29379
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472
About fp32 and fp16, this is the calculation precision of the neural network inference. fp32 refers to 32 bit floats, fp16 to 16 bit floats. It has been experimentally confirmed that the reduced floating point accuracy of 16 bit NN inference does not reduce playing strength for Lc0 significantly. However, there is not much point with GTX 10xx GPUs since those are not optimised for fp16. The RTX cards on the other hand are, in their case fp16 gains a large amount of speed as can be seen from those benchmarks.

As for how to use, it, you initialise Lc0 with "backend=cudnn-fp16" instead of "backend=cudnn".
How/where do you initialise LC0 with "backend=cudnn-fp16" ?

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Guenther
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Re: How good is the RTX 2080 Ti for Leela?

Post by Guenther » Wed Sep 26, 2018 12:52 pm

Lion wrote:
Wed Sep 26, 2018 12:38 pm
How/where do you initialise LC0 with "backend=cudnn-fp16" ?
It is just an uci option. (This question was already answered in this thread.)
Current foe list count : [91]
http://rwbc-chess.de/chronology.htm

Robert Pope
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Re: How good is the RTX 2080 Ti for Leela?

Post by Robert Pope » Wed Oct 17, 2018 6:34 pm

Now that the 2070 is out, I was wondering if we have confirmation that it will do FP16, and how it stacks up against the others:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000

             fp32    fp16    
Titan V:     13295   29379
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472

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Laskos
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Full name: Kai Laskos

Re: How good is the RTX 2080 Ti for Leela?

Post by Laskos » Thu Oct 25, 2018 7:03 am

Robert Pope wrote:
Wed Oct 17, 2018 6:34 pm
Now that the 2070 is out, I was wondering if we have confirmation that it will do FP16, and how it stacks up against the others:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000

             fp32    fp16    
Titan V:     13295   29379
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472
I have the same question. From the specifications, it seems it does support fp16, and will come at ~20,000 NPS, i.e. about 3-3.5 times faster than my GTX 1060. In a month or so I will have one, if what I said stands.

crem
Posts: 114
Joined: Wed May 23, 2018 7:29 pm

Re: How good is the RTX 2080 Ti for Leela?

Post by crem » Thu Oct 25, 2018 8:27 am

Updated information from Ankan on discord:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000
v0.17, default values for all other settings
(2070 run was with v0.18.1 lc0 build but with same settings)
             fp32    fp16    
GTX 1080Ti:   8996     -
Titan V:     13295   29379
RTX 2070:     8841   23721
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472
I'm not sure though whether it's fair to have v0.17 vs v0.18.1 comparison, don't remember which changes were there between..

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Laskos
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Full name: Kai Laskos

Re: How good is the RTX 2080 Ti for Leela?

Post by Laskos » Thu Oct 25, 2018 8:32 am

crem wrote:
Thu Oct 25, 2018 8:27 am
Updated information from Ankan on discord:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000
v0.17, default values for all other settings
(2070 run was with v0.18.1 lc0 build but with same settings)
             fp32    fp16    
GTX 1080Ti:   8996     -
Titan V:     13295   29379
RTX 2070:     8841   23721
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472
I'm not sure though whether it's fair to have v0.17 vs v0.18.1 comparison, don't remember which changes were there between..
Wow, thanks! RTX 2070 seems to be the best buy, and is about 4 times faster than my GTX 1060. Necessary procurement.

chrisw
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Joined: Tue Apr 03, 2012 2:28 pm

Re: How good is the RTX 2080 Ti for Leela?

Post by chrisw » Thu Oct 25, 2018 8:47 am

I just splashed out on a 2080ti new PC which is theoretically arriving in a few days. Am also wanting to get another 2080ti card to swap in or sit alongside the 1060 in my current PC. Anybody done a one for one replacement swap of these two? Any issues arise, or is it straightforward? Win10 btw. It’s amazing how resnet programming gets you into spending money!

Werewolf
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Joined: Thu Sep 18, 2008 8:24 pm

Re: How good is the RTX 2080 Ti for Leela?

Post by Werewolf » Thu Oct 25, 2018 8:48 am

Laskos wrote:
Thu Oct 25, 2018 8:32 am
crem wrote:
Thu Oct 25, 2018 8:27 am
Updated information from Ankan on discord:

Code: Select all

with cudnn 7.3 and 411.63 driver available at nvidia.com 
minibatch-size=512, network id: 11250, go nodes 1000000
v0.17, default values for all other settings
(2070 run was with v0.18.1 lc0 build but with same settings)
             fp32    fp16    
GTX 1080Ti:   8996     -
Titan V:     13295   29379
RTX 2070:     8841   23721
RTX 2080:     9708   26678
RTX 2080Ti:  12208   32472
I'm not sure though whether it's fair to have v0.17 vs v0.18.1 comparison, don't remember which changes were there between..
Wow, thanks! RTX 2070 seems to be the best buy, and is about 4 times faster than my GTX 1060. Necessary procurement.
It would get really interesting if you bought two of them and, perhaps, were quite a bit faster than a 2080 Ti

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