Computer Chess Club Archives




Subject: Re: PONDER=ON and TableBases on 1 PC

Author: Uri Blass

Date: 01:17:18 07/28/01

Go up one level in this thread

On July 28, 2001 at 01:12:41, Terry McCracken wrote:

>On July 27, 2001 at 18:58:30, Dann Corbit wrote:
>>On July 27, 2001 at 18:44:45, Roy Eassa wrote:
>>>On July 27, 2001 at 16:55:55, Dann Corbit wrote:
>>>>On July 27, 2001 at 16:51:08, Roy Eassa wrote:
>>>>>Be careful, Dann.  Dr. Hyatt has argued strongly that ponder should always be
>>>>>on, even with a single CPU.  (It seemed counter-intuitive to me too, but you
>>>>>should check out his recent postings -- over the past couple days, I think.)
>>>>Not when both engines play on the same machine.
>>>>No way.
>>>Yes way!  I reacted the same way (in my head), but I respect Dr. Hyatt and his
>>>arguments are worth reading at least!
>>If you run two engines which are both pondering on a single CPU machine, then
>>you are simply out of your mind.
>>I think you must have misread the arguments.
>No Dan he's read the arguements correctly!
>Posted by Robert Hyatt (Profile) on July 27, 2001 at 13:28:16:
>In Reply to: Re: Permanent Brain ON vs Permanent Brain OFF posted by Uri Blass
>on July 27, 2001 at 11:58:57:
>On July 27, 2001 at 11:58:57, Uri Blass wrote:
>>On July 27, 2001 at 11:18:08, Miguel A. Ballicora wrote:
>>>On July 26, 2001 at 14:41:54, Robert Hyatt wrote:
>>>>On July 26, 2001 at 12:55:06, Miguel A. Ballicora wrote:
>>>>>On July 26, 2001 at 10:43:45, Robert Hyatt wrote:
>>>>>>On July 26, 2001 at 09:56:24, Matthias Gemuh wrote:
>>>>>>>Hi Robert,
>>>>>>>I think you just wanted to make a joke. We all know that PONDER OFF hurts nobody
>>>>>>>(Fritz used its full time). PONDER ON on one CPU is very appropriate to arrive
>>>>>>>at wrong engine comparasons.
>>>>>>>>>>>both will get 1/2 of the machine and the time controls won't be screwed up.
>>>>>>ponder=off exposes the opportunity for a program to get into time trouble
>>>>>>because it assumes it will save time with ponder=on when it really can't since
>>>>>>it is disabled...
>>>>>Why the program should assume that it will save time in with ponder=on when
>>>>>it knows that it is off already?
>>>>>Shouldn't a program take this into account?
>>>>>If ponder=off is an option for the program, it should notice the difference
>>>>>and act accordingly IMHO.
>>>>because in my case, 99.9% of all games played have ponder=on.  I only disable
>>>>pondering to debug so that I can reproduce the same searches over and over
>>>>when necessary.  Since almost all real games are played with ponder=on, I don't
>>>>have a special time-allocation formula for ponder=on and another one for
>>>>ponder=off.  I just have one that _assumes_ ponder=on.
>>>>I see no reason to waste what little time I have working on something that is
>>>>hardly going to be used...
>>>Well, it is used a lot actually by lots of people already. Most of the people
>>>are running matches with ponder=off for some reasons.
>>>If both engines were tuned for ponder=off, it will be the best condition to
>>>optimze the resources since time used pondering is never as good a time used
>>>thinking. For instance, you have a competitive mindset in your answer but if my
>>>purpose is to run a match between engines to learn a particulat opening, I want
>>>my resources to be used as efficient as possible. That is ponder=off for both.
>>>Maybe you could consider making Crafty to be able to process "ponder=off"
>>>accordingly because there will be users that would benefit from it.
>>Crafty is not a commercial program so I guess that the way that users use it is
>>not important for Bob.
>>I also do not think that the difference between ponder on and ponder off is more
>>than 20 elo in most of the practical cases.
>I disagree.   When this first cropped up a couple of years ago, I ran a test,
>gnuchess on a single-cpu, vs crafty on a quad pentium-pro 200, but using only
>one cpu.  The quad was far slower than the 500mhz single cpu by a significant
>amount.  The match was pretty even (ponder=on) even though crafty had a much
>slower processor.  With ponder=off, the match was way more lop-sided in favor
>of GNU because crafty would get into time trouble and near the end of the
>time period it would have to move too quickly to avoid losing on time.
>It was _clearly_ worse.  And by more like 100 points, too.  I adjusted it a bit
>to help, but I have _never_ invested as much time in the ponder=off timing as
>I have in the ponder=on timing.  And I never will, any more than I am going to
>try to tune my son's mustang to run on a road coarse when we only take it to
>the 1/8th and 1/4th mile drag strips...
>I think you should spend the time making it optimal in the way it will normally
>be used, not in oddball configurations...
>I ran a bunch of games, everything equal but the hardwar
>Quote/Hyatt; Nope... no joke at all.  Two programs, one machine, my preference
>is ponder=on.

Note that it is hyatt's opinion.
I said that in most of the practical cases the difference between ponder on and
ponder off is not more than 20 elo.

The practical cases are usually with the commercial programs.
I am not talking about amatuers like GNUchess.

I agree that there may be a big difference with amatuers.
One reason is simply the fact that part of the amatuers do not know to ponder so
ponder off is clearly better for them than ponder on.

I do not know if this was the reason for GNU chess but when I read 100 elo
difference I suspect that this is the reason.

I do not believe that program are handicapped by more than 100 elo if they do
not know to ponder.

I believe that the difference is even less than 70 elo(70 elo is the difference
from doubling the speed of the program and it is better to be twice faster and
play without pondering).


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