Search found 610 matches

by petero2
Sun Jan 05, 2020 10:55 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: RMO - Randomized Move Order - yet another Lazy SMP derivate
Replies: 114
Views: 20479

Re: RMO - Randomized Move Order - yet another Lazy SMP derivate

Peter, have you seen my latest results. ... You said it is a mix of ABDADA + Lazy so that d/d+1 is a potential problem ... My implementation does not use the classical d/d+1 scheme: * I disabled the lazy SMP "depth + 1" trick, as I don't know if that makes sense in combination with ABDADA. Disablin...
by petero2
Sun Jan 05, 2020 1:14 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: RMO - Randomized Move Order - yet another Lazy SMP derivate
Replies: 114
Views: 20479

Re: RMO - Randomized Move Order - yet another Lazy SMP derivate

I think it still needs to be established that Lazy indeed searches a substantially wider tree (this is testable to some extent). It is not very obvious to me which mechanism might cause this as all the threads use basically the same search. Has anyone ever tested SHT-2 threads vs SHT-1 thread at fi...
by petero2
Mon Dec 30, 2019 2:56 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Trying to understand check evasion move generation.
Replies: 4
Views: 1128

Re: Trying to understand check evasion move generation.

I'm trying to understand Texel's check evasion move generation so I can implement something similar in my engine. https://github.com/B4dT0bi/texel/blob/master/src/moveGen.cpp I think I mostly understand it but there are a couple of things I'm not sure about. validTargets |= pos.pieceTypeBB(OtherCol...
by petero2
Mon Oct 28, 2019 8:15 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Another take on DTS?
Replies: 20
Views: 4290

Re: Another take on DTS?

BTW, for the record, this was the idea from Harry Nelson (one of the Cray Blitz team) way way back... Tim Mann re-discovered it when porting Crafty to the Alpha. Not sure whether he found Harry's old paper that mentioned it, or if he re-discovered it on his own. In either case, It was not "my" idea...
by petero2
Mon Oct 28, 2019 6:15 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Another take on DTS?
Replies: 20
Views: 4290

Re: Another take on DTS?

* Each cluster node has its own local transposition table, which works the same as in a normal SMP engine. In Texel's case I use your lockless hashing algorithm. Thanks for inventing that. What's this lockless hashing algorithm? I'm definitely interested in it. Lockless hashing has also been referr...
by petero2
Sun Oct 27, 2019 10:02 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Another take on DTS?
Replies: 20
Views: 4290

Re: Another take on DTS?

Nothing wrong with that. EXCEPT that you are accepting a significant performance degradation (no global transposition table) ... The nice thing about SMP/NUMA implementations is that the latency is near zero for SMP and not a whole lot higher for reasonable NUMA configurations. It is certainly true...
by petero2
Sun Oct 27, 2019 6:16 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Another take on DTS?
Replies: 20
Views: 4290

Re: Another take on DTS?

Shared transposition tables on a cluster have been discussed many times. It is something that can work in theory, but in practice it has some serious issues. The most important of which is the incredible latency for inter-nodal message-passing. Maybe "(partially) shared TT" is not the correct termi...
by petero2
Sun Oct 27, 2019 1:13 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Another take on DTS?
Replies: 20
Views: 4290

Re: Another take on DTS?

Of course lazy SMP is useless on a cluster that lacks a shared TT, but DTS and YBWC will also suffer without a shared TT. But it is possible to implement a (partially) shared TT even without shared memory, by using message passing, as demonstrated here . So lazy SMP is not useless on a cluster that...
by petero2
Sun Oct 27, 2019 12:59 am
Forum: Computer Chess Club: General Topics
Topic: longest 6-man EGTB win
Replies: 40
Views: 5933

Re: longest 6-man EGTB win

Anyone have a list of positions of the longest 6-man EGTB wins that meet 50 move rule requirements? I.E. no cursed wins allowed I think to do this accurately, you must have the complete Lomonosov files. They have distance to mate. But they don't take into account the 50-move rule. Whenever they sho...
by petero2
Sat Oct 05, 2019 10:08 am
Forum: Computer Chess Club: General Topics
Topic: Can YOU compile this engine?
Replies: 8
Views: 2188

Re: Can YOU compile this engine?

Can you PLEASE make a ANDROID version of Honey-X5i/Crystal-Honey-X5i engine? I put the source code for Honey-X5i into the DroidFish source tree and was able to compile the engine with a one line change in the source code. Here are the compiled files: https://www.dropbox.com/s/4t2vm6nykc9y07o/honey_...