Author: Uri Blass
Date: 00:11:41 10/18/02
Go up one level in this thread
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
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