Search found 729 matches

by xr_a_y
Sat Oct 12, 2019 5:20 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: kiwipete perft position
Replies: 52
Views: 7443

Re: kiwipete perft position

Hi hi hi my class ChessPiece still exists but only containing constants and static methods now. Took three years to get there. Can you imagine how many bugs and time I would have saved when I would have taken the right design decision from start. So for beginners who do object oriented programming:...
by xr_a_y
Sat Oct 12, 2019 4:11 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: On-line engine blitz tourney October
Replies: 24
Views: 837

Re: On-line engine blitz tourney October

Sorry, cant be here this time. Have fun.
by xr_a_y
Sat Oct 12, 2019 12:28 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: 76th Amateur Series Division 4
Replies: 30
Views: 2194

Re: 76th Amateur Series Division 4

Big thanks, as always very fun and instructive.
by xr_a_y
Sat Oct 12, 2019 6:05 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Looking for TT policy advice
Replies: 23
Views: 1269

Re: Looking for TT policy advice

Why would you want to store the score part? A hash move should always be searched first. An age field would be useless on an always-replace (or an under-cut) slot. And two bits would probably be large enough for it, so it could be easily packed with the bound-type flag, (whick also only needs 2 bit...
by xr_a_y
Fri Oct 11, 2019 7:51 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Looking for TT policy advice
Replies: 23
Views: 1269

Re: Looking for TT policy advice

Vivien, Have you considered that the problem with long TC is not related to hash usage but rather to prunning conditions that are triggered differently in longer controls? I cannot really answer yes to that question ... It may indeed be the case. Are you thinking of a particular parameter ? I thoug...
by xr_a_y
Fri Oct 11, 2019 5:39 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Looking for TT policy advice
Replies: 23
Views: 1269

Re: Looking for TT policy advice

Sure, a large part of the hash key is completely redundant, as it can only be the index of the entry. Usually storing 32 bits as signature is good enough, and I was told Stockfish even uses only 16 bits. Wasting memory on padding is of course never a good idea. Only or very large or complex variant...
by xr_a_y
Fri Oct 11, 2019 4:50 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Looking for TT policy advice
Replies: 23
Views: 1269

Re: Looking for TT policy advice

Yes but as the struct is ill-organized there is some padding in the middle. That can be optimized in first place.
by xr_a_y
Fri Oct 11, 2019 2:54 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Looking for TT policy advice
Replies: 23
Views: 1269

Re: Looking for TT policy advice

I suppose you mean "with only two slots per bucket". True, you don't have much leeway in that case, as it is very important to always store in the TT. You could use undercut replacement, replacing the highest depth of the pair rather than the lowest when the new depth is exactly one less. Or do tha...
by xr_a_y
Thu Oct 10, 2019 5:34 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Looking for TT policy advice
Replies: 23
Views: 1269

Re: Looking for TT policy advice

At short TC the entire tree often fits in the TT, so the replacement algorithm does not matter as it is hardly exercised. My exprience is that you only start to notice a slowdown if you shrink the TT size to less than 10% of the node count, even with rather simple replacement schemes. For running w...
by xr_a_y
Wed Oct 09, 2019 4:41 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Igel 1.9.0 64-bit 4CPU Gauntlet for CCRL 40/40
Replies: 5
Views: 222

Re: Igel 1.9.0 64-bit 4CPU Gauntlet for CCRL 40/40

Guenther wrote:
Wed Oct 09, 2019 3:02 pm
xr_a_y wrote:
Wed Oct 09, 2019 1:24 pm
The 4CPU version is weaker than the 1 CPU one ?
Seems to be in line with what the author told together with the 2.00 release.
viewtopic.php?f=2&t=69754&start=360#p814436
Indeed, thanks