TalkChess.com

Posted: **Sun Jun 28, 2020 7:52 am**

AMD Ryzen Threadripper 3990X, 64 cores, 128 threads
Komodo 14 POPCNT vs Komodo 14 POPCNT, default, C0, 128 MB Hash, TC = 10 + 0.1 sec, 3000 games
Stockfish 11 POPCNT vs Stockfish 11 POPCNT, default, C0, 128 MB Hash, TC = 10 + 0.1 sec, 3000 games

Komodo 14

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Threads    2 vs 1          4 vs 2          8 vs 4          16 vs 8        32 vs 16        64 vs 32       128 vs 64
Elo          88              68              61               43             29              28              -1
Draw %      66.2            71.4            74.3             77.7           81.7            84.1            85.3
W-D-L   879-1986-135    718-2142-140    645-2229-126    520-2331-149    401-2451-148    360-2522-118    216-2559-225

Stockfish 11

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Threads    2 vs 1          4 vs 2         8 vs 4           16 vs 8         32 vs 16       64 vs 32       128 vs 64
Elo          63              61             44                38              24             26               5
Draw %      70.8            72.7           77.5              80.1            84.6           86.1            88.2
W-D-L   709-2124-167    669-2180-151    525-2326-149    464-2403-133    336-2537-127    321-2582-97     199-2646-155

tpm = time per move, d = depth, nps = nodes per second

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Komodo 14 T1      (tpm=218.0 d=19.07 nps=  2.184.031)
Komodo 14 T2      (tpm=214.8 d=20.52 nps=  4.356.131) - (tpm=219.6 d=20.38 nps=  4.371.401)
Komodo 14 T4      (tpm=217.7 d=21.72 nps=  8.598.857) - (tpm=221.8 d=21.58 nps=  8.427.235)
Komodo 14 T8      (tpm=222.9 d=23.01 nps= 17.083.765) - (tpm=220.0 d=22.89 nps= 16.319.575)
Komodo 14 T16     (tpm=224.5 d=24.06 nps= 30.843.341) - (tpm=225.8 d=24.44 nps= 33.266.657)
Komodo 14 T32     (tpm=224.1 d=24.77 nps= 57.449.961) - (tpm=222.8 d=25.60 nps= 73.557.642)
Komodo 14 T64     (tpm=214.5 d=26.26 nps=145.082.937) - (tpm=216.2 d=26.17 nps=145.036.085)
Komodo 14 T128    (tpm=200.2 d=25.29 nps=215.777.613)

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Stockfish 11 T1   (tpm=215.7 d=22.64 nps=  1.965.980)
Stockfish 11 T2   (tpm=212.1 d=25.49 nps=  3.851.322) - (tpm=211.4 d=24.46 nps=  4.008.706)
Stockfish 11 T4   (tpm=208.1 d=26.95 nps=  7.746.021) - (tpm=210.0 d=26.11 nps=  8.278.643)
Stockfish 11 T8   (tpm=207.2 d=28.15 nps= 15.410.676) - (tpm=207.4 d=27.96 nps= 18.544.535)
Stockfish 11 T16  (tpm=206.4 d=29.14 nps= 35.251.188) - (tpm=205.3 d=29.64 nps= 32.642.384)
Stockfish 11 T32  (tpm=205.1 d=30.18 nps= 59.852.477) - (tpm=203.6 d=30.64 nps= 77.849.924)
Stockfish 11 T64  (tpm=202.0 d=32.04 nps=147.277.339) - (tpm=202.3 d=31.59 nps=142.762.608)
Stockfish 11 T128 (tpm=201.9 d=31.20 nps=213.444.223)

Posted: **Sun Jun 28, 2020 9:54 am**

Surely the result of 128 v 64 will be impacted by moving from physical cores to logical cores..?

I think Dual EPYCs could still show a decent gain at 128 threads

Posted: **Sun Jun 28, 2020 11:03 am**

Werewolf wrote: ↑Sun Jun 28, 2020 9:54 am Surely the result of 128 v 64 will be impacted by moving from physical cores to logical cores..?
I think Dual EPYCs could still show a decent gain at 128 threads

In general the the number of cores are only physical cores or (physical + logical) cores?

Posted: **Sun Jun 28, 2020 4:12 pm**

The AMD Ryzen Threadripper 3990X has 64 cores and 128 (hypertreading) threads.

Posted: **Sun Jun 28, 2020 6:54 pm**

So with Contempt off for both engines, Komodo gained more than Stockfish for every doubling of real cores. It seems that using Contempt significantly inflates the advantages of more cores, due to reducing draws.

Posted: **Wed Jul 01, 2020 10:32 am**

fastgm wrote: ↑Sun Jun 28, 2020 4:12 pm The AMD Ryzen Threadripper 3990X has 64 cores and 128 (hypertreading) threads.

I do not ask you for the parameters of 3990x but I ask you, you used SMT or not used SMT at every point of your measurement.
If you would not use SMT at Threads = 2 the Elo difference would be higher between 1 Thread and 2 Threads and the full curve wuld be smaller about ~10% and maybe the curve of Elo would be more monotonous.

Posted: **Wed Jul 01, 2020 11:41 am**

The subject speaks for itself, core doubling.
Up to 64 = physical cores, 128 = hyperthreading threads

2 vs 1, 4 vs 2 ... 64 vs 32 physical cores and the last test
128 hyperthreading threads vs 64 physical cores

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Elo gain by core doubling - Komodo 14, Stockfish 11 - Contempt 0

Elo gain by core doubling - Komodo 14, Stockfish 11 - Contempt 0

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Re: Elo gain by core doubling - Komodo 14, Stockfish 11 - Contempt 0

Re: Elo gain by core doubling - Komodo 14, Stockfish 11 - Contempt 0

Re: Elo gain by core doubling - Komodo 14, Stockfish 11 - Contempt 0

Re: Elo gain by core doubling - Komodo 14, Stockfish 11 - Contempt 0