Search found 678 matches

by OliverBr
Mon Jun 21, 2021 7:09 pm
Forum: Computer Chess Club: General Topics
Topic: Multi-threaded shortest mate solver
Replies: 24
Views: 9710

Re: Multi-threaded shortest mate solver

lechmazur wrote:
Wed May 19, 2021 1:02 am
I'm afraid that finding the shortest possible mates wouldn't improve Stockfish's strength at all
You are correct about this. Problem solving and playing games are two different things. Playing games needs a lot of pruning.
by OliverBr
Tue Jun 15, 2021 8:04 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Problems with pruning non-PV nodes
Replies: 2
Views: 1227

Re: Problems with pruning non-PV nodes

Thank you, @mar for your reply. You have got my issue on the point. better move ordering as well (especially for quiets because trying better moves first makes them less likely to be over-reduced/pruned in LMR/LMP) Absolutely correct! a general observation I made is that the better current (pv) move...
by OliverBr
Sun Jun 13, 2021 6:56 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Problems with pruning non-PV nodes
Replies: 2
Views: 1227

Problems with pruning non-PV nodes

The following position 8/3q3k/1p1r3p/2rp1Rn1/p2NpQP1/2P3P1/PP6/3R3K w - - 2 38 8/3q3k/1p1r3p/2rp1Rn1/p2NpQP1/2P3P1/PP6/3R3K w - - 2 38 has a strong singular winning move 38. Kg2 and this line: Kg2 Rg6 Rh1 Qe7 Re5 Qf6 Qxf6 Rxf6 Rxg5 Engines do have problems finding this move. But, when you give the m...
by OliverBr
Fri Jun 11, 2021 9:34 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

OliThink 5.9.9 has been released. Finally it features half-sized bitboards and some minor changes that improved the engine a little while being even smaller. The original targets of OliThink are still valid: - Just mobility evaluation. - No pre-calculated data. - Compact and efficient. OliThink 5.9....
by OliverBr
Mon Jun 07, 2021 8:25 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

Finally, only 6 bits are used instead of 7. I am expecting a 5 ELO gain from this. bits or bitboards(U64)? 6 bits. You only need to know the inner 6 bits of a file/rank in order to calculate the possible sliding moves. Including 5.9.8 OlIThink is precomputing 7 bits which is more than necessary. Th...
by OliverBr
Sun Jun 06, 2021 9:35 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

Bitboard enthusiasts may be interested in the latest change in the bitboard implementation of OliThink. Finally, only 6 bits are used instead of 7. I am expecting a 5 ELO gain from this. https://github.com/olithink/OliThink/commit/78fa794f777bd5e851fc0abbcfc1bca22e6c0dcf Note: When I first implement...
by OliverBr
Sun Jun 06, 2021 6:36 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

50K games would run for days and days on end... I can't do that yet, until I have a dedicated computer to run those tests. (I don't want to run them on my laptop, to be honest.) If you use a 16 core engine and small time controls (e.g. 40/12), it can be done in much less time. That's what I am doin...
by OliverBr
Sun Jun 06, 2021 1:06 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

I have never understood this. Sometimes, I actually feel like CuteChess is rigging the tournaments. I thought it often, too, but it's actually not. Then I add a functionality to Rustic which speeds it up, but doesn't do anything otherwise, such as PVS or aspiration windows, and test this in a gaunt...
by OliverBr
Sun Jun 06, 2021 12:07 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

OliThink 5.9.8 has been released.

It has 50 lines fewer/less code, yet it is about 20 ELO stronger compared to 5.9.5.
by OliverBr
Thu May 27, 2021 5:11 pm
Forum: Computer Chess Club: General Topics
Topic: OliThink 5.9.5 is very small
Replies: 47
Views: 15245

Re: OliThink 5.9.5 is very small

OliThink 5.9.5d is over 50 lines smaller and it is more elegant, but is this worth -7 ELO? What do you think? If you are interested, here is the commit, that I haven't included in 5.9.6: https://github.com/olithink/OliThink/commit/f25e8d1913d950425021dcceb1c361c39904c6bc Actually that commit has a ...