Neurosis 2.2
Posted: 11 Jan 2007, 14:53Neurosis 2.2
Got tired of losing all the time, hate the holidayseason, so I decided to make my program more selective. Previously I tried to be as strong as possible with hardly being selective, but I got stuck more or less. Now I wrote some sort of a tactical ply that only tries most tactical moves after normal searchdepth, with a lot of threatdetections when not to and try a regular ply instead. If the tactical ply gives a big threat instead (gave check, moved a pawn to 7th, etc.) it can call a regular search ply again for the other side to try to refute the threat. That is more efficient then it sounds and basically my program now finds most tactics and some strategical ideas one ply faster, while often not losing a ply in searchdepth over a version without this, also it improves my effective branchingfactor so it works really well at long timecontrols. Maybe not very good at fast timecontrols, I dunno. Does cost me about 20-30% in nps. (~160Knps on PIV-2.4gHz now.
)
Max hashtable size you can set increased from 64 to 128MB.
Mate-score-ranges changed, (First versions used 99.98/-99.98 for a mate in 1, but that's small if the user decides to insert a bunch of queens for example. Then I switched to 319.98/-319.98, and now to 299.98/-299.98) because of a new internal margin where I want to avoid checking not to cross the 16bit integer limit. Atleast Arena also announces the correct mate-in-N number with these scores.
Draw claims to Winboard by insufficient material added, (only K vs K and K+minor piece vs K) was never bothered about that but figured I'd add it sometime.
New endgame knowledge, tweaks and several speedups.
http://www.geocities.com/tasteofinsanit ... rosis.html
(Also on Leo Dijksman's WBEC website later I think. (Thx!) )
Stan
Got tired of losing all the time, hate the holidayseason, so I decided to make my program more selective. Previously I tried to be as strong as possible with hardly being selective, but I got stuck more or less. Now I wrote some sort of a tactical ply that only tries most tactical moves after normal searchdepth, with a lot of threatdetections when not to and try a regular ply instead. If the tactical ply gives a big threat instead (gave check, moved a pawn to 7th, etc.) it can call a regular search ply again for the other side to try to refute the threat. That is more efficient then it sounds and basically my program now finds most tactics and some strategical ideas one ply faster, while often not losing a ply in searchdepth over a version without this, also it improves my effective branchingfactor so it works really well at long timecontrols. Maybe not very good at fast timecontrols, I dunno. Does cost me about 20-30% in nps. (~160Knps on PIV-2.4gHz now.
)
Max hashtable size you can set increased from 64 to 128MB.
Mate-score-ranges changed, (First versions used 99.98/-99.98 for a mate in 1, but that's small if the user decides to insert a bunch of queens for example. Then I switched to 319.98/-319.98, and now to 299.98/-299.98) because of a new internal margin where I want to avoid checking not to cross the 16bit integer limit. Atleast Arena also announces the correct mate-in-N number with these scores.
Draw claims to Winboard by insufficient material added, (only K vs K and K+minor piece vs K) was never bothered about that but figured I'd add it sometime.
New endgame knowledge, tweaks and several speedups.
http://www.geocities.com/tasteofinsanit ... rosis.html
(Also on Leo Dijksman's WBEC website later I think. (Thx!) )
Stan
For now it's always just one ply, and that means the risk is just one ply as well, that is one reason why I like it. Basically this is similair to reducing most quiet moves (and speeding up finding most tactical lines) at the leaves by 1 ply, but in reverse. (but that's just a matter of implementation) 