Author: Robert Hyatt
Date: 21:15:43 12/08/00
Go up one level in this thread
On December 08, 2000 at 23:13:13, Landon Rabern wrote: >On December 08, 2000 at 22:22:24, Robert Hyatt wrote: > >>On December 08, 2000 at 20:41:40, Landon Rabern wrote: >> >>>On December 08, 2000 at 16:16:01, Robert Hyatt wrote: >>> >>>>On December 08, 2000 at 13:21:21, Peter Fendrich wrote: >>>> >>>>>On December 08, 2000 at 13:06:43, Robert Hyatt wrote: >>>>> >>>>>>On December 08, 2000 at 12:56:09, Peter Fendrich wrote: >>>>>> >>>>>>>I looking for a measurement for move generation performance. >>>>>>> >>>>>>>Do you think FH/CountNodes, where FH is number of times the first generated move >>>>>>>was a Fail High, is a good measurement? >>>>>>>Do you have some other? >>>>>>>What's your figures? >>>>>>>I get some 50% and I have a feeling it's to low. >>>>>>> >>>>>>>//Peter >>>>>> >>>>>> >>>>>>The critical statistic I measure in crafty is this: "For any position where >>>>>>I 'fail high' (return a score >= beta) what percentage of the time does it >>>>>>happen on the _first_ move?" I generally average 92%. Anything over 90% is >>>>>>reasonable. Anything less means move ordering needs work. >>>>> >>>>>OK, it seems logical. I have in princple 3 types of FH: >>>>> 1) Hash table (without moving) >>>>> 2) Null Move >>>>> 3) Ordinary moves (including the hash table move) >>>>> >>>>>Do you include all these cases? >>>>>With only the third case counted I'm well over 90% >>>>> >>>>>//Peter >>>> >>>> >>>>Only 1 and 3. 2 is done at a different place in the search and doesn't >>>>really count in "move ordering". >>>> >>>>Actually, the way you wrote it, only 3 counts. for 1) you are not searching >>>>a move, so that can't be counted. 2) doesn't count either... >>> >>>I am getting about 80% on this, is this real bad? I am not doing internal >>>interative deepening, do you think this will help a lot, or do you think there >>>is something else wrong. >>> >>>I try moves in this order: >>> >>>hash/pv >>>all captures sorted MVV/LVA >>>two killers >>>3 history scan moves >>>the rest >>> >>> >>>Regards, >>> >>>Landon W. Rabern >> >> >>Your MVV/LVA ordering is probably the culprit. Because you are trying moves >>like QxP, even though the pawn is defended... and you try those _before_ you >>try the move that will ultimately fail high (a killer or history move). >> >>I would still expect it to be higher than 80%... but that might be about right >>with MVV/LVA. You get some of that back in terms of faster ordering, and you >>get some back because the bad captures get cut off quickly by null-move >>searches... but it could be better... > >Ok, I switched to using my SEE to order the moves, but did not do the bad >captures last yet(no time yet), just did them all at once, but ordered with SEE. > Now I get about 86%-89%. Do you think I should be able to get over 90% by >doing bad captures last? > >Regards, > >Landon W. Rabern Very possibly...
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