Author: Robert Hyatt
Date: 21:00:17 10/17/02
Go up one level in this thread
On October 17, 2002 at 20:50:55, Uri Blass wrote: >On October 17, 2002 at 18:21:06, Robert Hyatt wrote: > >>On October 17, 2002 at 11:34:35, Uri Blass wrote: >> >>>On October 17, 2002 at 10:41:20, Robert Hyatt wrote: >>> >>>>On October 17, 2002 at 06:13:26, Johan Melin wrote: >>>> >>>>>On October 16, 2002 at 23:35:10, Robert Hyatt wrote: >>>>> >>>>>>On October 15, 2002 at 14:01:35, Johan Melin wrote: >>>>>> >>>>>>>On October 14, 2002 at 07:34:16, Bas Hamstra wrote: >>>>>>> >>>>>>>>Bob, did you read the Hsu transcript posted here? It is pretty clear to me that >>>>>>>>Hsu himself says 12 ply fullwidth *total*. Case closed. Please read the complete >>>>>>>>transcript. >>>>>>>> >>>>>>>>Best regards, >>>>>>>>Bas. >>>>>>> >>>>>>>I agree. The transcript with Hsu is clear. But it would be out of character for >>>>>>>CCC if everybody just agreed with each other, there still has to be a fight ... >>>>>>>;) >>>>>>> >>>>>>>/Johan Melin >>>>>> >>>>>> >>>>>>Here is the relevant part of the transcript: >>>>>> >>>>> >>>>>There are other relevant parts? How about: >>>>> >>>>>---------------------------------- >>>>>EeEk(* DM) kibitzes: kib question from ardee: Does "12(6)" mean 12 >>>>>total ply or 12+6=18 total ply? This has the been source of huge >>>>>arguments for years! >>>>>CrazyBird(DM) kibitzes: 12 total in terms of brute force. 6 is just >>>>>the max partition in hardware. >>>>>---------------------------------- >>>>> >>>>>He sais 12 _total_. He also refers to 6 as "just", implying that it is less >>>>>important than the 12. >>>> >>>> >>>>No he clearly did _not_ say "12 total". He said "12 plies of brute force". He >>>>also >>>>said elsewhere that the _hardware_ does forward pruning. So "12 plies of brute >>>>force" >>>>implies that is non-hardware... >>> >>>It is not clear from it. >>> >>>suppose the hardware never pruned in the first 3 plies in the hardware when the >>>hardware get depth 6. >> >>I don't disagree, although I know how the hardware was implemented, and it isn't >>nearly >>so clean to try to be asymmetric based on search depth. This is basically a >>finite state machine >>and it makes far more sense for everything to be done the same way, from ply 1 >>to ply N, >>inside the hardware... >> >> >>>Suppose also that the software sent the hardware only lines of at least 9 moves. >>>You can have 12 plies of brute force when 6 is the maximal depth in the >>>hardware. >> >>Sure. That is why the question needs to be posed properly rather than the vague >>questions >>that were asked the last time... >> >> >>>> >>>> >>>> >>>>> >>>>>If somebody tells you that "the storage capacity of this harddrive is 20 GB, 5 >>>>>GB is just the linux partition", then what is the storage capacity? 25 GB? >>>> >>>>No. But nobody has said that. they have said "20 gigabytes of space". >>>>The hardware has 5 gigabytes of buffer." Does the thing have 20 gigs or >>>>25 gigs _now_??? From a speed perspective, it matters how that is done. >>>> >>>> >>>>> >>>>>---------------------------------- >>>>>EeEk(* DM) kibitzes: question from parabola444: You mentioned Deep >>>>>Blue searched about 12 plies brute force + extensions, which is >>>>>similar to what pc programs these days get on a fast pc - since Deep >>>>>Blue hardware was much faster, how come it didn't search significantly >>>>>deeper ? >>>>>CrazyBird(DM) kibitzes: to all the book readers, if you do like the >>>>>book, please tell your friends would might be interested. thanks. >>>>>CrazyBird(DM) kibitzes: replace would with who:). >>>>>CrazyBird(DM) kibitzes: we were using fairly extensive search >>>>>extensions, and the decision not to use null move pruning was an >>>>>deliberate one. >>>>>---------------------------------- >>>>> >>>>>The interesting part here is not just what he says, but what he doesn't say. If >>>>>they search 18 plies nominal, he would have said so. Why would he hold back such >>>>>a statement? He indirectly agrees to searching only 12 plies. >>>> >>>>Again, Hsu tries to answer what he is asked, as briefly as possible. The >>>>hardware does >>>>forward pruning. They have _always_ given the "software depth" when they >>>>discuss >>>>this kind of number. Whether he still is is up for debate, but I doubt he would >>>>suddenly >>>>change his terminology after using it for 15 years... >>>> >>>> >>>> >>>> >>>>> >>>>> >>>>>>----------------------------------------------------------------------------------------------------------------------- >>>>>>CrazyBird(DM) kibitzes: 12(6) means 12 plies of brute force (not >>>>>>counting the search extensions & quiescence). >>>>>>CrazyBird(DM) kibitzes: 6 means the maximum hardware search depth >>>>>>allowed. >>>>>>CrazyBird(DM) kibitzes: this means that the PV could be up to 6 plies >>>>>>deeper before quiescence. >>>>>>----------------------------------------------------------------------------------------------------------------------- >>>>> >>>>>Note that in the first line he states "not counting ..." but does not mention >>>>>any extra plies from hardware. Wouldn't 6 plies be more significant than >>>>>quiescence? So why doesn't he mention that it isn't included in the 12 plies? >>>>> >>>> >>>>What about the last sentence. It seems to say exactly what you say is missing. >>>> >>>>"up to 6 plies deeper". >>> >>>up to 6 plies deeper relative to the logfile. >>>I do not know if they did extensions in the hardware but even if I assume that >>>they did ply can include also extensions. >>> >>>When people says that the program search 6 plies it includes extensions so it is >>>possible that when 6 plies are missing it includes extensions. >> >>But "up to 6" then means "no more than 6 plies of extensions." I _know_ that >>they >>allowed two plies of extensions for every 2 plies of search, which means that a >>2 >>ply search could go to 40+ plies if needed... >> >>The "up to 6" doesn't fit there at all... > > >My guess is that Hsu meant that the pv could be 6 plies deeper before quiescence >and extensions but forgot to say the word extensions >> >> >>> >>> >>>> >>>> >>>> >>>> >>>>>> >>>>>>OK, some questions: >>>>>> >>>>>>1. If 12(6) means 12 plies total, with 6 done in hardware, how do you reconcile >>>>>>that >>>>>>_last_ sentence above (the PV could be up to 6 plies _deeper_ before >>>>>>quiescence). >>>>>>Deeper than what? Only possible answer is deeper than 12 plies. >>>>> >>>>>He is talking about the PV. Their hardware return a score, but no PV. So >>>>>sometimes they didn't get a complete PV, and say "the pv COULD BE UP TO ...". >>>> >>>> >>>> >>>>That makes no sense. They don't limit the 12 ply search to 6 plies of >>>>extensions >>>>total. So he is not talking about search extensions. Saying "the PV could >>>>be up >>>>to 6 plies deeper" is _obviously_ not a reference to the missing pv from the >>>>hardware >>>>for many reasons. First, if the hardware is searching 6 plies, the PV would not >>>>be >>>>"up to 6 plies more" it would be "at _least_ 6 plies more because of the >>>>hardware search >>>>extensions + qsearch". >>> >>> >>>> >>>> >>>>> >>>>>> >>>>>>2. If 12(6) means 12 plies total, with 6 in hardware, what does 4(5) mean? 4 >>>>>>plies total >>>>> >>>>>Uri Blass suggests aggresive extensions that increase the remaining depth. >>>> >>>>Again, that makes no sense in this context. It would _instantly_ have to resort >>>>to a >>>>hardware-chip only search if the above means 4 plies brute force, 5 plies of >>>>that done >>>>by hardware. >>> >>>I do not see the problem. >>> >>>It is possible that deeper blue extended 4 plies for the first 3 plies so the >>>first 3 plies were done in the software and the last 5 plies were done in the >>>hardware. >> >>Then vincent's 4(5) can't possibly be right either. Hsu _clearly_ said 4 means >>4 >>plies of "brute-force" search. Whatever the hardware does, it does at _every_ >>ply, >>so the 4(5) explanation you are proposing just doesn't fit... > >I do not try to defend vincent explanation but to explain how it is possible to >get 4 plies by normal definition when 5 is the maximal depth of the hardware. > >Suppose that the software searches in some line 3 plies and the remaining depth >after the 3 plies is 5 thanks to extension. > >It means that the normal depth of the search was 4 and the maximal depth of the >hardware was 5. > >Uri We know some specifics. We know that the hardware didn't do 1-2 ply searches. It couldn't because it finished so quickly the SP2 couldn't keep up. Therefore, this still doesn't work...
This page took 0.01 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.