Author: Landon Rabern
Date: 12:40:28 12/09/00
Go up one level in this thread
On December 09, 2000 at 00:15:43, Robert Hyatt wrote: >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... Are you counting beta cutoffs in the q-search as well?
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