Search found 16726 matches

by bob
Tue Aug 14, 2018 9:03 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: A more interesting question about GPU verses CPU
Replies: 16
Views: 1184

Re: A more interesting question about GPU verses CPU

To 'compare' algorithms you should first define a metric for algorithmic complexity. You seem to focus (completely arbitrarily) on the number of multiplications. One might just as well only consider the number of branches. With the same number of branches per second, Stockfish would not be a match ...
by bob
Tue Aug 14, 2018 8:52 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Time Management and Move Selection
Replies: 14
Views: 1272

Re: Time Management and Move Selection

My current "easy move" approach is really just a "easier/harder" approach. If things are stable, the situation looks "easier". If things are unstable, the situation looks "harder". That degree of stability can make the search move significantly faster, or significantly slower. Very "un-computer-like...
by bob
Tue Aug 14, 2018 4:18 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Attacks From table
Replies: 12
Views: 1060

Re: Attacks From table

unless you have a power of 2 size, a table lookup is going to include a multiply. Shift and add really don't count in a super-scalar architecture. I don't think there is anything to gain here. I used to do what Slate and Atkin did. Maintained an array of attacks. One showing all squares attacked fro...
by bob
Tue Aug 14, 2018 4:28 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Attacks From table
Replies: 12
Views: 1060

Re: Attacks From table

Getting rid of that overhead is what drove me to the rotated bit board development. And then magic move generation came along as yet another alternative. The updates to maintain both attacks to and attacks from (slate/atkin chapter in Frey's "Chess Skill in Man and Machine") were pretty expensive. C...
by bob
Wed Jul 25, 2018 3:06 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: UCI Hash Usage Rules
Replies: 60
Views: 3667

Re: UCI Hash Usage Rules

May or may not be what you want. RSS = Resident Set Size. This is the set of pages the program currently has in real memory. Might or might not be the actual "working set" as some of the pages might be swapped out. Also RSS is the set of physical pages in memory for a process. There can be overlap w...
by bob
Wed Jul 25, 2018 3:01 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Time Management and Move Selection
Replies: 14
Views: 1272

Re: Time Management and Move Selection

I think you need to give up on "easy move" itself. Leads to problems. What if your opponent finds a deep tactic that lets it hang a piece, but it takes a deep search to realize this? Easy move code can make you do the capture and get blown out. There are things you can try, with risks. For example, ...
by bob
Fri Jul 20, 2018 4:09 am
Forum: Computer Chess Club: General Topics
Topic: how will Leela fare at the WCCC?
Replies: 176
Views: 11409

Re: how will Leela fare at the WCCC?

one famous one was a limit on number of processors, were the limit was completely arbitrary and announced at the last minute. Never understood that and it was eliminated the next year...
by bob
Wed Jul 18, 2018 8:10 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: UCI Hash Usage Rules
Replies: 60
Views: 3667

Re: UCI Hash Usage Rules

VM usage has never been real accurate. It is quite difficult to determine what is duplicated and what is not. And that answer changes as the program executes and causes copy-on-write duplications. And then there is the shared memory stuff if you use processes. Looks like each process is huge when in...
by bob
Tue Jul 17, 2018 12:57 am
Forum: Computer Chess Club: General Topics
Topic: how will Leela fare at the WCCC?
Replies: 176
Views: 11409

Re: how will Leela fare at the WCCC?

Couple of points... There has been a solution for this. If program A offers a draw ITSELF, that is supposed to be passed on to program B, IF it can process the request. Then no human intervention is possible. The idea is that a program should be able to play a completely legal game of chess all by i...
by bob
Tue Jul 17, 2018 12:40 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: UCI Hash Usage Rules
Replies: 60
Views: 3667

Re: UCI Hash Usage Rules

I don't quite follow what that "threads are more resource heavy under linux." In fact, it is the exact opposite. Threads intentionally share everything, where processes (via fork()) share very little (at least they share executable code and anything that is not modified - an artifact of the "copy o...