Search found 16845 matches

by bob
Wed Dec 18, 2019 4:20 am
Forum: Computer Chess Club: General Topics
Topic: Engine's "ELO" revisited
Replies: 38
Views: 2328

Re: Engine's "ELO" revisited

Most of the time I play 5 min+ 3 sec./move time increment. Last 8 games I lost 7-1 to Prodeo 2.4. :shock: I also want to try Bob's Crafty 25.3 , but I think it is hard to set the crafty.rc file to a similar level. Shredder's adaptive function is good, I'm playing hard games with an old Android tabl...
by bob
Mon Dec 16, 2019 2:47 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Graph History Interaction 2 questions
Replies: 9
Views: 829

Re: Graph History Interaction 2 questions

It is a problem that seems to be unsolvable without completely killing hash table usage and the associated endgame performance gains... And it affects EVERY program that uses hashing.
by bob
Tue Dec 10, 2019 3:33 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Misprediction-poor looping
Replies: 9
Views: 658

Re: Misprediction-poor looping

One other thing. Modern hardware can predict 100% on loops that are less than N iterations. Not sure what N is today, a few years ago it was 10-12 depending on the microprocessor. If the iteration count is reasonably long, you get N-1 predictions and 1 misprediction for each time you execute the loo...
by bob
Sun Dec 08, 2019 6:24 pm
Forum: Computer Chess Club: General Topics
Topic: stockfish 10 vs. Mephisto III S Glasgow
Replies: 116
Views: 8616

Re: stockfish 10 vs. Mephisto III S Glasgow

How do you let modern programs run on 68030 hardware ? That's the point. New hardware capabilities lead to new software capabilities. IE Cray Blitz runs terribly on a PC. It runs like the blazes on a Cray, even if the hardware clock speeds are the same. We did a lot of cute stuff with vectors that ...
by bob
Sun Dec 08, 2019 3:21 am
Forum: Computer Chess Club: General Topics
Topic: stockfish 10 vs. Mephisto III S Glasgow
Replies: 116
Views: 8616

Re: stockfish 10 vs. Mephisto III S Glasgow

One other note. The engine evolved along with the hardware. IE we can do things today, thanks to the faster hardware, than we could do back in the sub 1000 NPS days. So the comparison is not exactly fair...
by bob
Wed Dec 04, 2019 4:14 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 20
Views: 3139

Re: Limiting nodes to reduce engine strength

Crafty has played >10,000 games against GMs on ICC. But that is just one data point. It also needs players on the middle and lower end of the Elo range, and that is hard to find AND validate since lots of weaker players use computers to assist them. I have something that seems to work where the Elo ...
by bob
Thu Nov 14, 2019 8:53 pm
Forum: Computer Chess Club: General Topics
Topic: Syzygy tbs bug
Replies: 9
Views: 809

Re: Syzygy tbs bug

How can a TB handle that? It simply looks up a position and gives the score. It doesn't know about past game history. That is up to the program to handle. IE if the move is a 3-fold repetition, why bother looking it up in the database? IE in crafty, I check for repetitions first. If found, I return ...
by bob
Fri Nov 08, 2019 5:42 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 20
Views: 3139

Re: Limiting nodes to reduce engine strength

I am still working on getting reliable (within my testing framework) Elo for 2800, 2600, 2400 ... It is not exactly easy. I have not fiddled with extensions and reductions as of yet, because I believe that reducing the NPS far enough will do effectively the same thing. Since I only have a check exte...
by bob
Thu Nov 07, 2019 7:47 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 20
Views: 3139

Re: Limiting nodes to reduce engine strength

This is hard. Where do I find such humans? Certainly not on ICC since so many use computers there. If we had enough tournaments here in Birmingham, I might try that but it would probably cause objections. The 1800 version might well be much stronger against humans, disrupting the 1800-1999 class com...
by bob
Thu Nov 07, 2019 6:12 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 20
Views: 3139

Re: Limiting nodes to reduce engine strength

Not a fan of a depth limit, since they can occasionally be quite "coarse" in terms of time. I have a pretty decent NPS idea in the works. I have normalized on 2800 Elo == 6M nodes per second (on my MacBook). Elo scales down the NPS and introduces evaluation randomness. And it is actually working pre...