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Comparative nodes per second
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Robert Hyatt



Joined: 27 Feb 2006
Posts: 15816
Location: Birmingham, AL
PostPost subject: Re: Comparative nodes per second    Posted: Thu Apr 12, 2012 11:26 pm Reply to topic Reply with quote
dchoman wrote:
bob wrote:
Don wrote:
jdart wrote:
Quote:
What about for deciding whether to try null move or not? I don't see how Crafty could avoid calling the eval in the main search.


No eval test is done in Crafty as a condition for null move. Arasan does not do this either. The efficacy of this is questionable.

--Jon


For us there is no question. We have tried many permutations of the general idea from always doing the null move test regardless of the evaluation to restricting it to certain node types, etc.

What has always worked best is to do null move pruning test only when the current evaluation is already >= beta. A lot of details in each program that could change this formula of course - but for us it's not a close enough call to even be ambiguous.

What does Arasan do? Do you always do the null move test?


I decided to give this a cluster test since that is one option I do not recall having tried in real games. Initially, with a few positional tests, it actually looks like a reasonable idea (I just added && eval >= beta to the end of the rest of the null-move qualifiers such as not being in check, the hash table didn't say null is futile, etc..., so that the eval call is not done on every node, just the ones that pass the earlier filters). Reduced the size of the tree, and slowed the nps. But with a net gain on just a few test positions. Am now running a cluster test to see if it is a real gain in terms of Elo...

More in a couple of hours...


I tried this in EXchess a few weeks ago and it was a small net win. One thing I realized is that it should not slow down the program very much because I would need to do an eval anyway if the null move drops straight into qsearch. So if the eval >= beta, and I do the null move, I keep the score and just use it (with the sign flipped) when qsearch is called rather than repeat the eval.

- Dan


First run completed and showed "0 elo improvement" but one takes that with the +/-4 error bar to be not so conclusive. Running another 30K games to refine the accuracy somewhat...

If it sticks at 0 gain, I am done. If it shows some promise, I might try to optimize a bit. But I have tried so many things with null-move in the past, this was almost certainly one of them, and there's generally a reason something is not in my code like that, in that it simply didn't work for me. I am going to look at this a bit further to see if there are any other potential things to try, again..
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Subject Author Date/Time
Comparative nodes per second Larry Kaufman Tue Apr 10, 2012 7:49 pm
      Re: Comparative nodes per second Vincent Diepeveen Tue Apr 10, 2012 8:16 pm
      Re: Comparative nodes per second Marco Costalba Tue Apr 10, 2012 8:41 pm
            Re: Comparative nodes per second Larry Kaufman Tue Apr 10, 2012 9:02 pm
                  Re: Comparative nodes per second Thomas Petzke Tue Apr 10, 2012 9:30 pm
            Re: Comparative nodes per second Richard Vida Tue Apr 10, 2012 10:15 pm
                  Re: Comparative nodes per second Larry Kaufman Tue Apr 10, 2012 10:18 pm
                        Re: Comparative nodes per second Sam Hamilton Tue Apr 10, 2012 10:54 pm
                        Re: Comparative nodes per second Richard Vida Tue Apr 10, 2012 11:28 pm
                              Re: Comparative nodes per second Larry Kaufman Wed Apr 11, 2012 4:52 am
            Re: Comparative nodes per second Don Dailey Wed Apr 11, 2012 11:23 pm
                  Re: Comparative nodes per second Don Dailey Wed Apr 11, 2012 11:50 pm
                        Re: Comparative nodes per second Sam Hamilton Thu Apr 12, 2012 12:07 am
      Re: Comparative nodes per second Robert Hyatt Tue Apr 10, 2012 9:31 pm
            Re: Comparative nodes per second Larry Kaufman Tue Apr 10, 2012 9:35 pm
                  Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 1:10 am
      Re: Comparative nodes per second Daniel Shawul Tue Apr 10, 2012 11:41 pm
            Re: Comparative nodes per second Larry Kaufman Wed Apr 11, 2012 5:05 am
                  Re: Comparative nodes per second Sam Hamilton Wed Apr 11, 2012 5:28 am
                        Re: Comparative nodes per second Marco Costalba Wed Apr 11, 2012 5:58 am
                              Re: Comparative nodes per second Larry Kaufman Wed Apr 11, 2012 1:04 pm
                  Re: Comparative nodes per second Daniel Shawul Wed Apr 11, 2012 12:27 pm
      Re: Comparative nodes per second Jon Dart Wed Apr 11, 2012 1:59 pm
            Re: Comparative nodes per second Sam Hamilton Wed Apr 11, 2012 2:25 pm
                  Re: Comparative nodes per second Larry Kaufman Wed Apr 11, 2012 2:36 pm
                        Re: Comparative nodes per second Jon Dart Wed Apr 11, 2012 3:06 pm
            Re: Comparative nodes per second Larry Kaufman Wed Apr 11, 2012 2:28 pm
                  Re: Comparative nodes per second Jon Dart Wed Apr 11, 2012 3:10 pm
                        Re: Comparative nodes per second Larry Kaufman Wed Apr 11, 2012 3:59 pm
                              Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 1:19 am
                  Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 1:15 am
                        Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 1:35 am
                              Re: Comparative nodes per second Sam Hamilton Thu Apr 12, 2012 2:32 am
                                    Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 2:50 am
                                          Re: Comparative nodes per second Sam Hamilton Thu Apr 12, 2012 3:10 am
                                                Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 3:35 am
                              Re: Comparative nodes per second Jon Dart Thu Apr 12, 2012 2:37 pm
                                    Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 3:24 pm
                                          Re: Comparative nodes per second Jon Dart Thu Apr 12, 2012 4:25 pm
                                                Re: Comparative nodes per second Don Dailey Thu Apr 12, 2012 4:33 pm
                                                      Re: Comparative nodes per second Jon Dart Thu Apr 12, 2012 4:41 pm
                                                      Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 8:13 pm
                                                            Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 9:00 pm
                                                            Re: Comparative nodes per second Daniel Homan Thu Apr 12, 2012 9:52 pm
                                                                  Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 11:26 pm
                                                                        Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 11:40 pm
                                                                              Re: Comparative nodes per second Sam Hamilton Thu Apr 12, 2012 11:51 pm
                                                                              Re: Comparative nodes per second Robert Hyatt Sat Apr 14, 2012 4:23 am
                                                                        Re: Comparative nodes per second Uri Blass Sat Apr 14, 2012 5:05 pm
                                                                              Re: Comparative nodes per second Robert Hyatt Sat Apr 14, 2012 6:46 pm
                                                                                    Re: Comparative nodes per second Don Dailey Sat Apr 14, 2012 6:56 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Sun Apr 15, 2012 4:31 am
                                                                                    Re: Comparative nodes per second Larry Kaufman Sat Apr 14, 2012 7:47 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Sun Apr 15, 2012 4:36 am
                                                                                          Re: Comparative nodes per second Larry Kaufman Sun Apr 15, 2012 4:47 am
                                                                                          Re: Comparative nodes per second Robert Hyatt Mon Apr 16, 2012 7:14 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Tue Apr 17, 2012 3:02 pm
                                          Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 6:50 pm
                                                Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 8:12 pm
                                                      Re: Comparative nodes per second Robert Hyatt Sat Apr 14, 2012 4:28 am
                                                            Re: Comparative nodes per second Larry Kaufman Sat Apr 14, 2012 4:45 am
                                                                  Re: Comparative nodes per second Robert Hyatt Sat Apr 14, 2012 4:46 pm
                                                                        Re: Comparative nodes per second Larry Kaufman Sat Apr 14, 2012 5:10 pm
                                                                              Re: Comparative nodes per second Sam Hamilton Sat Apr 14, 2012 5:35 pm
                                                                              Re: Comparative nodes per second Robert Hyatt Sun Apr 15, 2012 4:38 am
                                                                                    Re: Comparative nodes per second Larry Kaufman Sun Apr 15, 2012 4:51 am
                                                                                          Re: Comparative nodes per second Robert Hyatt Mon Apr 16, 2012 7:20 pm
                                                                                    Re: Comparative nodes per second Don Dailey Sun Apr 15, 2012 12:14 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Mon Apr 16, 2012 7:21 pm
                                                                  Re: Comparative nodes per second Uri Blass Sat Apr 14, 2012 5:17 pm
                                                                        Re: Comparative nodes per second Larry Kaufman Sat Apr 14, 2012 5:22 pm
                                                                              Re: Comparative nodes per second Uri Blass Sat Apr 14, 2012 5:36 pm
                                                                                    Re: Comparative nodes per second Larry Kaufman Sat Apr 14, 2012 5:47 pm
                                    Re: Comparative nodes per second Sam Hamilton Thu Apr 12, 2012 4:49 pm
                                          Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 5:14 pm
                                                Re: Comparative nodes per second Jon Dart Thu Apr 12, 2012 6:00 pm
                                                      Re: Comparative nodes per second Uri Blass Thu Apr 12, 2012 6:37 pm
                                                            Re: Comparative nodes per second Jon Dart Thu Apr 12, 2012 6:50 pm
                                                            Re: Comparative nodes per second Uri Blass Thu Apr 12, 2012 6:53 pm
                                                                  Re: Comparative nodes per second Lucas Braesch Sun Apr 15, 2012 4:56 am
                                                                        Re: Comparative nodes per second Uri Blass Sun Apr 15, 2012 5:16 am
                                                                              Re: Comparative nodes per second Lucas Braesch Sun Apr 15, 2012 7:58 am
                                                                        Re: Comparative nodes per second Don Dailey Sun Apr 15, 2012 1:10 pm
                                                                              Re: Comparative nodes per second Uri Blass Sun Apr 15, 2012 2:48 pm
                                                                                    Re: Comparative nodes per second Don Dailey Sun Apr 15, 2012 3:26 pm
                                                                                    Re: Comparative nodes per second Robert Hyatt Tue Apr 17, 2012 5:17 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Tue Apr 17, 2012 6:05 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Tue Apr 17, 2012 7:11 pm
                                                                                          Re: Comparative nodes per second Don Dailey Tue Apr 17, 2012 6:06 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Tue Apr 17, 2012 6:16 pm
                                                                                          Re: Comparative nodes per second Don Dailey Tue Apr 17, 2012 6:45 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Tue Apr 17, 2012 6:55 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Tue Apr 17, 2012 7:16 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Tue Apr 17, 2012 7:25 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Tue Apr 17, 2012 7:59 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Tue Apr 17, 2012 8:14 pm
                                                                                          Re: Comparative nodes per second Miguel A. Ballicora Tue Apr 17, 2012 10:33 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Tue Apr 17, 2012 10:51 pm
                                                                                          Re: Comparative nodes per second Vincent Diepeveen Wed Apr 18, 2012 12:12 am
                                                                                          Re: Comparative nodes per second Sam Hamilton Wed Apr 18, 2012 12:28 am
                                                                                          Re: Comparative nodes per second Miguel A. Ballicora Wed Apr 18, 2012 2:28 am
                                                                                          Re: Comparative nodes per second Sam Hamilton Wed Apr 18, 2012 4:32 am
                                                                                          Re: Comparative nodes per second Miguel A. Ballicora Wed Apr 18, 2012 4:44 am
                                                                                          Re: Comparative nodes per second Miguel A. Ballicora Tue Apr 17, 2012 10:28 pm
                                                                              Re: Comparative nodes per second José C. Martínez Galán Wed Apr 18, 2012 6:16 am
                                                                                    Re: Comparative nodes per second Robert Hyatt Thu Apr 19, 2012 9:53 pm
                                                                                    Re: Comparative nodes per second Don Dailey Thu Apr 19, 2012 10:22 pm
                                                                                          Re: Comparative nodes per second José C. Martínez Galán Thu Apr 19, 2012 10:49 pm
                                                                                          Re: Comparative nodes per second Robert Hyatt Thu Apr 19, 2012 11:21 pm
                                                                                          Re: Comparative nodes per second Marco Costalba Fri Apr 20, 2012 5:18 am
                                                                                          Re: Comparative nodes per second Michel Van den Bergh Fri Apr 20, 2012 6:10 am
                                                                                          Re: Comparative nodes per second Miguel A. Ballicora Fri Apr 20, 2012 11:35 am
                                                                                          Re: Comparative nodes per second Don Dailey Fri Apr 20, 2012 10:57 am
                                                                                          Re: Comparative nodes per second Marco Costalba Fri Apr 20, 2012 1:58 pm
                                                                                          Re: Comparative nodes per second Sam Hamilton Fri Apr 20, 2012 2:19 pm
                                                                                          Re: Comparative nodes per second Miguel A. Ballicora Fri Apr 20, 2012 2:29 pm
                                                                                          Re: Comparative nodes per second Don Dailey Fri Apr 20, 2012 3:13 pm
                                                                                          Re: Comparative nodes per second Don Dailey Fri Apr 20, 2012 4:52 pm
                                                                                          Re: Comparative nodes per second Uri Blass Sat Apr 21, 2012 6:03 am
                                                                                          Re: Comparative nodes per second Marco Costalba Sat Apr 21, 2012 8:14 am
                                                                                          Re: Comparative nodes per second Ed Schroder Sat Apr 21, 2012 10:50 am
                                                                                          Re: Comparative nodes per second Marco Costalba Sat Apr 21, 2012 11:13 am
                                                                                          Re: Comparative nodes per second Don Dailey Fri Apr 20, 2012 12:31 pm
                                                                                          Re: Comparative nodes per second Dan Andersson Fri Apr 20, 2012 4:14 pm
                                                                                          Re: Comparative nodes per second Don Dailey Fri Apr 20, 2012 4:38 pm
                                                            Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 7:10 pm
                                                Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 6:55 pm
                                                      Re: Comparative nodes per second (early results) Robert Hyatt Thu Apr 12, 2012 7:36 pm
                              Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 7:13 pm
                                    Re: Comparative nodes per second Larry Kaufman Thu Apr 12, 2012 8:18 pm
                                          Re: Comparative nodes per second Robert Hyatt Thu Apr 12, 2012 8:55 pm
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