Glaurung 2 and SMP

Discussion of chess software programming and technical issues.

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Tord Romstad
Posts: 1808
Joined: Wed Mar 08, 2006 9:19 pm
Location: Oslo, Norway

Re: Glaurung 2 and SMP

Post by Tord Romstad »

hcyrano wrote:Tord,

have you statistics (nodes, time, ... ) on Glaurung's code with 1, 2, 4, 8... cores?
Hello Bruno,

Unfortunately, I have no such statistics. I have a dual-core CPU, but one of the cores is usually busy with some other task, so I very rarely have the chance to test my engine with more than one thread. Except for a single tournament two years ago, when I operated my engine remotely on a quad-core Linux machine, I have never even seen Glaurung run on more than 2 cores.

The only useful data I have are the results on the CEGT and CCRL rating lists. Based on the difference in strength between 1 CPU and 4 CPUs on these lists, it looks like the effective speedup with four threads is approximately 3.0.

Tord