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perejaslav wrote:Your opinions about the Rybka Cluster Mental ...

You got that right my man

I am quite sure this Cluster thing is DOA (Dead On Arrival), even if it were free what's the value of analysis, which don't show real depth/node speed? Example:

[D]2K3k1/1p6/R3p1p1/1rB1P1P1/8/8/1Pb5/8 w - -

Analysis by Rybka Cluster 296 Cores :

1.Rc6 bxc6 2.b4 Be4 3.Kc7 Kf7 4.Kc8 Bd5 5.Kc7 Ke8 6.Kc8 Bh1 7.Kc7 Kf7 8.Kc8 Bg2
-+ (-4.84) Depth: 27 00:04:58 6371mN
1.Rc6 bxc6 2.b4 Be4 3.Kc7 Kf7 4.Kc8 Bd5 5.Kc7 Ke8 6.Kc8 Bh1 7.Kc7 Kf7 8.Kc8 Bg2 9.Kc7 Bd5 10.Kc8
-+ (-4.84) Depth: 27 00:05:25 6961mN

Analysis by Critter 0.90 64-bit 2 cores :

1.Rc6 bxc6 2.b4 Be4 3.Kd7 Kf7 4.Kc7 Ke8 5.Kc8 Bg2 6.Kc7 Bd5 7.Bd6 Be4 8.Bc5 Bf3 9.Kc8 Bd5 10.Kc7 Bg2 11.Bd6 Kf7 12.Bc5 Be4 13.Kc8 Bd5 14.Kc7 Rxc5 15.bxc5 Ke7 16.Kc8 Be4
-+ (-3.72) Depth: 27/48 00:00:44 138mN, tb=12795
1.Rc6 bxc6 2.b4 Be4 3.Kd7 Kf7 4.Kc7 Ke8 5.Kc8 Bg2 6.Kc7 Bd5 7.Bd6 Be4 8.Bc5 Bf3 9.Kc8 Bd5 10.Kc7 Bg2 11.Kc8 Bf3 12.Kc7
-+ (-3.72) Depth: 28/48 00:00:57 183mN, tb=21085

Jouni

Hey, that's not fair test, Critter is using GTB, Rybka is using none...

Gian-Carlo Pascutto wrote: Because the parallel efficiency will suck compared to a real parallelized tree search (which I presume Rybka Cluster is using, or it wouldn't be so strong).

Of course, some people here are willing to believe it when the Aquarium guys claim perfect speedups with IDeA, so if you truly believe that then what you propose is better. (And you'll get your ass kicked if you try to play a game with this "perfect speedup" solution)

I agree that the engine CPU distribution will be better than GUI.

However, there might be an economic tradeoff. Say its twice as worse. EC2 cluster running twice as long or with twice as many machines might be a possible alternative. We are not playing a game but analyzing some critical positions. The real question is how much worse is this on average for position analysis? If its 2-3 times worse, it might still well be cheaper to use a standard cluster.

A good thing but in my opinion much to expensive and therefore only interesting for people who do not care about money.
Kurt