Author: Robert Hyatt
Date: 11:58:38 04/06/04
Go up one level in this thread
On April 05, 2004 at 16:31:41, Gerd Isenberg wrote: >On April 05, 2004 at 16:29:00, Gerd Isenberg wrote: > >>On April 05, 2004 at 15:51:43, Robert Hyatt wrote: >> >>>On April 05, 2004 at 15:02:56, Gerd Isenberg wrote: >>> >>>>On April 05, 2004 at 14:11:34, Robert Hyatt wrote: >>>> >>>>>On April 05, 2004 at 12:27:50, rasjid chan wrote: >>>>> >>>>>>On April 05, 2004 at 11:05:30, Robert Hyatt wrote: >>>>>> >>>>>>Thanks, but I don't need to test yet as you have tested ! >>>>>> >>>>>>I think using nodes searched should be good. >>>>>>If a move fails low with very few nodes searched, it probably >>>>>>mean being rejected easily, so sort low. >>>>>> >>>>>>Rasjid >>>>> >>>>>Correct most of the time. Sometimes a move will have a high node count just >>>>>because there are lots of checks and extensions. But I've been sorting by node >>>>>counts for 15+ years with good results, of course forcing the PV move to always >>>>>be at the top regardless of its node count... >>>>> >>>> >>>>I use node count per root move too. >>>>What about following "enhancement": >>>>If PV changes, to store (some) "previous" PV moves and to use them early after >>>>current PV move, regardless of their node counts? >>> >>> >>>It is worth testing. It didn't work for me in crafty or Cray Blitz, but it >>>might work for another program. I always had the best luck overall by just >>>using pure node counts... >>> >>>It helps the most when there is a "best" move that you won't find until deeper >>>depths. It will percolate up the list, iteration by iteration, so that it is >>>near the top on the iteration where it becomes best. I also use this >>>information in my parallel split/dont-split at the root adaptive algorithm in >>>Crafty... >> >> >Yes, exactly my experience. Anyway i occasionally noticed a former PV move had >low node count (e.g. a forced draw line) but a new PV move suddenly fails below >draw score. Im such cases trying the "safe" drawline earlier may help to save >some time. It would be very rare, but you _could_ handle that directly. Flag the move as "draw", if the first root move produces a score < 0, then try the drawing move next. If the first move is > 0, leave the drawing move in its normal place in the search order. But, as I said, that has to be pretty rare...
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