Author: Vincent Diepeveen
Date: 17:09:19 09/20/05
Go up one level in this thread
On September 20, 2005 at 16:35:43, Robert Hyatt wrote: >On September 20, 2005 at 16:22:58, Vincent Diepeveen wrote: > >>On September 20, 2005 at 15:27:14, Bruce Moreland wrote: >> >>>On September 20, 2005 at 13:16:35, Robert Hyatt wrote: >>> >>>>On September 20, 2005 at 12:59:03, Uri Blass wrote: >>>> >>>>>On September 20, 2005 at 11:58:35, Robert Hyatt wrote: >>>>> >>>>>>On September 20, 2005 at 02:35:50, Bruce Moreland wrote: >>>>>> >>>>>>>On September 18, 2005 at 14:47:26, Robert Hyatt wrote: >>>>>>> >>>>>>>>On September 18, 2005 at 14:38:27, Uri Blass wrote: >>>>>>>> >>>>>>>>>On September 18, 2005 at 13:59:18, Robert Hyatt wrote: >>>>>>>>> >>>>>>>>>>On September 18, 2005 at 12:00:09, Vincent Diepeveen wrote: >>>>>>>>>> >>>>>>>>>>>On September 18, 2005 at 10:45:19, Robert Hyatt wrote: >>>>>>>>>>> >>>>>>>>>>># Name 1 2 3 4 5 P BU SB G >>>>>>>>>>>1 Deep Thought II 2w1 5b0 7w1 3b1 5b1 4 13½ 11 5 >>>>>>>>>>>2 Zarkov 1b0 6b1 4w1 5b= 3w1 3½ 15 9¾ 5 >>>>>>>>>>>3 Star Socrates 10w1 7b1 5w1 1w0 2b0 3 12½ 5 5 >>>>>>>>>>>4 Now 6w= 10b= 2b0 8w1 9b1 3 10½ 5½ 5 >>>>>>>>>>>5 Mchess Pro 8b1 1w1 3b0 2w= 1w0 2½ 16½ 7¾ 5 >>>>>>>>>>>6 Cray Blitz 4b= 2w0 9w1 7b0 10w1 2½ 11 4 5 >>>>>>>>>>>7 Wchess 9w1 3w0 1b0 6w1 8b0 2 13½ 4½ 5 >>>>>>>>>>>8 Evaluator 5w0 9b0 10w1 4b0 7w1 2 10 2½ 5 >>>>>>>>>>>9 Innovation II 7b0 8w1 6b0 10b1 4w0 2 10 2½ 5 >>>>>>>>>>>10 Spector 3b0 4w= 8b0 9w0 6b0 ½ 12½ 1½ 5 >>>>>>>>>>> >>>>>>>>>>>Zarkov from those days had no problems beating your 3 million nps Cray Blitz. >>>>>>>>>>>Nor had Wchess problems beating your 3 million nps Cray Blitz. >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>>Ask John about the game. First, this was a 500K program for rounds 2-4. And >>>>>>>>>>when you ask him, he'll tell you about our rather severe crash problem due to a >>>>>>>>>>missing test to limit ply to 64 or less. And in a couple of cute places, we >>>>>>>>>>went beyond that limit, crashed, and burned. We fixed it for the last round, >>>>>>>>>>but it really didn't matter to the final results. >>>>>>>>>> >>>>>>>>>>But notice the issue was about deep thought, _not_ about Cray Blitz. Did you >>>>>>>>>>see any of the micros coming close? (hint: round 2 was a forfeit which is why >>>>>>>>>>they were paired a second time, round 2 never got started for the DT MCP game). >>>>>>>>> >>>>>>>>>Deep Thought was significantly better than the micro of 1995 >>>>>>>>> >>>>>>>>>Uri >>>>>>>> >>>>>>>>I am well aware of that. And DB was 100x faster than deep thought 2, and also >>>>>>>>had a better evaluation... >>>>>>>> >>>>>>>>that was my point in all this... >>>>>>> >>>>>>>I think that Hsu is a pretty arrogant person, after having read some stuff that >>>>>>>he has said about himself and other chess programmers. >>>>>>> >>>>>>>Read his book, if you can stand it. >>>>>> >>>>>>I did. It didn't particularly turn me off. But then I have had dozens of >>>>>>face-to-face conversations with him dating back to 1987 in Orlando at the ACM >>>>>>event that year, continuing thru the point where he left IBM a few years back. >>>>>> >>>>>>> >>>>>>>For years you have taken a few things he has said as truth, but given his >>>>>>>personality I am not sure if they are true. He may think they are, but this >>>>>>>doesn't mean that they are. >>>>>> >>>>>>That is probably all in perception. I took very little of what he said at face >>>>>>value, without supporting evidence. He was usually more than happy to sit down >>>>>>with deep thought and play with positions to see how it would react. And he >>>>>>never wanted to "hide" the display so I could not see. I didn't trust the SE >>>>>>data, since they gave conflicting reports on the effect (was it +70 or +7 rating >>>>>>points better) so I simply tried it for myself in Cray Blitz. And I think that >>>>>>+7 was closer to the truth although in the right positions it was much more than >>>>>>that... >>>>>> >>>>>> >>>>>> >>>>>> >>>>>>> >>>>>>>He hung you out to dry by leaving you as primary defender of Deep Blue for >>>>>>>years, while he left the trivialities of computer chess to mere mortals like us. >>>>>>> The DB project doesn't deserve defense. It hit computer chess like a >>>>>>>carpetbagger, then left in the night when the money was gone. >>>>>>> >>>>>>>bruce >>>>>> >>>>>> >>>>>>However, I would not attribute that to Hsu or Campbell. They were active in >>>>>>computer chess for many years. IBM pulled the plug for obvious reasons after >>>>>>they hit the peak of Mt. Everest... >>>>>> >>>>>>I'll always have a great deal of respect for the group. PVS search was first >>>>>>used in my program by accident, as Murray and I played with it at an ACM event >>>>>>on a machine we were not using, but a machine we had to use due to a power loss >>>>>>during a key round. Singular Extensions was Hsu's idea, and it certainly >>>>>>worked, since many are using it today in various forms. >>>>> >>>>>I know nobody who use it in the way that Hsu used it. >>>>> >>>>>Uri >>>> >>>> >>>>Several have used PV-singular as defined by Hsu. Kittinger was one, Lang was >>>>another. I'm not sure anyone did the FH-singular extension as defined by Hsu >>>>because it is _very_ costly. But I did it in Cray Blitz and it worked just >>>>fine. I tried it in Crafty and it didn't work just fine. Whether that was a >>>>result of the null-move stuff with R=2/3, vs Cray Blitz with R=1, I don't really >>>> know since I was not interested in crippling Crafty's search to try them >>>>further... >>>> >>>>One day I might, again... >>>> >>>>However, just because no one did FH-singular doesn't mean the idea is wrong. No >>>>one does it because of the cost. When you are 1000x faster than your nearest >>>>competitor, you can give up a factor of 10x to implement something like that, >>>>and _still_ be 100x faster than them which is more than enough to avoid >>>>trouble... >>>> >>>>People copy ideas that work well with low cost, they often avoid things with >>>>high cost because that cost will more than offset the gain if you don't have >>>>special-purpose hardware to hold the cost down. I could make a list of a few >>>>key endgame features that appeared in Crafty before they were in any commercial >>>>programs. Outside passed pawns in 1995 is one. Then candidate passed pawns >>>>(distant majorities). etc. If you go back to 1976 and "blitz" we had the >>>>"passed pawn race" code already in place so that we could detect uncatchable >>>>passed pawns in king and pawn endings. Most everyone does that today. Because >>>>the costs are more than offset by the gains. FH-singular might not be there >>>>yet, but that is why no one is using it, not that it does not work. Because it >>>>is clearly correct theoretically. Just too expensive practically... >>> >>>It also mean that it does work. When your competition is out-gunned, everything >>>you do works, including the stuff that doesn't work. >>> >>>This is not to say that the stuff doesn't work. If you want an example of >>>someone who does FH singular extension, albeit in restricted form, look at me. >>>When I fail high I keep searching at reduced depth, although not all the time. >>> >>>DT/DB may have been a great system. I don't know, because I don't trust the >>>information that I have seen about it, and I can't examine it for myself. >>> >>>I don't trust the DB guys to make the determination. You can listen to any >>>number of people talk about how their program is super-advanced and does this >>>and that, and when you play the program on equivalent hardware, it sucks. >>> >>>Hardware can mask a lot of problems. Essentially you said so yourself when you >>>talked about DB "giving up a factor of 10" to SE. >>> >>>I would be absolutely insane to "give up a factor of 10". My program gives up a >>>ply due to its use of SE, but it doubles its tactical speed. So I gave up >>>nothing -- SE doubles my program's speed, by my estimation, despite reducing its >>>average depth. That is the world I operate in. If something makes my program >>>suck, I have to remove it, because I can't afford to suck, because other people >>>who don't suck have big enough hammers that they can break my skull if I do. >>>This is very Darwinian. Something that is occupies a niche by itself can afford >>>to be inefficient. Once it has competitors who make use of the same resources, >>>it had better become efficient unless it wants to end up obsolete. >>> >>>Honestly, none of the big iron seems very efficient to me. You invented a lot >>>of techniques, and you deserve to be one of the first few guys in the CC hall of >>>fame, but I bet you got a lot better when you had to fight Fritz on equal >>>footing. >>> >>>bruce >> >>Please realize 1 factor. At 480 cpu's using SE is very difficult. >> >>The huge number of tiny searches it generates are a major problem. >> >>In fact i made special splitting code in order to be able to use SE at a quad >>even. It scales the program better already at a quad. At 16 cpu's i couldn't run >>with SE initially without making the special splitting code. >> >>Above 16 cpu's, forget using SE. Too many tiny searches. >> >>SE loses diep less than a ply usually. Usually about 0.5 ply. The problem i have >>with SE is that in testgames it scores better without SE, because that 0.5 ply >>is an extra "positional 0.5 ply" whereas SE is just tactical and at 14 ply >>search depths there is no magic tactics that win the game suddenly. >> >>Only in testsets there is. >> >>Additional SE sees tactics after the game has been decided already. When you >>need it, like in seeing perpetual check, something that does make sense to see, >>then it doesn't see it. >> >>Vincent > > >I don't believe your last statement has anything to do with reality. Bruce and >I played lots of games when we were both fiddling with SE. We played a big >batch with him using SE and me not. And in many games, suddenly BOOM, ferret >would find some deep tactical shot that I would not see until a couple of moves >later. Without SE, our depths were pretty similar, and our tactics were as >well. With SE, he was quite noticably stronger. However, Crafty on the other >hand was not. And before you start on q-search checks, this was at a time where >_neither_ were doing them.. I don't know if he does today or not. > >I'll remind you that 5 years ago you continually said (a) clusters can't work; >yet you used one; Huh? Want to call the 512 processor origin3800 a cluster? It's a supercomputer in any kind of respect. Note that todays clusters have a better latency than the supercomputers used to have. That changes things *bigtime*. >(b) SE is no good; yet you always claim to have it >implemented but usually turned off; Actually i had some selfinvented singular extension turned on in 1994-1996 then a much improved one was there in 2001 (thanks to bruce) until world champs 2005 it was turned on always in tournaments. Usually this is a last second decision to turn it on or off. I plan to turn it off for next tournament though, as i'm in home tests running right now without it and i like it. But the real bottom line is: If YOU believe SE works, knowing diep uses it, ferret uses it, what stops you from turning it on in crafty? You say it is a magic extension, yet you are the only one not having it turned on in tournaments. Then either your statement is false, or you're doing something wrong in crafty. *my* statement, after running with it for 4 years now is that at todays search depths in TOURNAMENTS at 4 cpu's or above, i see no point in using SE, because it does tactically improve an engine *usually*, but there is simply no trick there where you can win with. So it is a lost 0.5 - 1 ply search depth effectively. Vincent
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