Author: Robert Hyatt
Date: 11:59:09 10/18/02
Go up one level in this thread
On October 18, 2002 at 03:11:41, Uri Blass wrote: >On October 18, 2002 at 00:00:17, Robert Hyatt wrote: > >>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... > >In the example that I give the hardware did 5 plies search >and not 1-2 ply search so I still do not see the problem. > >It is possible that 5 plies is the maximal depth and >there were also cases >when the software asked the hardware to do 4 ply search >but not 1-2 ply search. > >Uri OK, then again tell me how 4(5) is going to always let the hardware do 5 ply searches (which I don't believe by the way as he said "up to 5 plies in hardware" recently) with only 4 plies of brute-force search. You can _not_ assume that there are extensions in the brute force search because in many positions, there are none...
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