Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Using a lot of computers against kramnik(is it possible?)

Author: Uri Blass

Date: 22:45:32 04/18/01

Go up one level in this thread


On April 18, 2001 at 17:48:01, Vincent Diepeveen wrote:

>On April 18, 2001 at 06:03:34, Uri Blass wrote:
>
>>On April 18, 2001 at 05:20:03, Vincent Diepeveen wrote:
>>
>>>On April 17, 2001 at 15:40:58, Uri Blass wrote:
>>>
>>>>Suppose program X is playing against kramnik.
>>>>
>>>>I think that it may be a good idea to generate a program that generates a tree
>>>>and sends all the positions in the tree to people who want to help the computer
>>>>in the match(I will call it the main program).
>>>>
>>>>The people give program X to analyze the position and return score and depth to
>>>>the main program.
>>>>
>>>>The main program is using all the information about scores and depthes to decide
>>>>about the best move.
>>>
>>>So a beginner rated 600 is very happy about a certain move,
>>>and as a real patzer he returns infinite score for his move.
>>
>>Sorry but a beginner is not going to give information.
>>Only program X is going to give depthes and score for positions and program X is
>>a constant program.
>>
>>If program X is a preprocessor it should be changed to get not only a position
>>to analyze but also to get the root position otherwise it is not going to
>>analyze position from the same point of view.
>
>I see no advantages in parallellizing a true preprocessor,
>but if you talk about wanting to parallellize a program, then it's
>obvious that you need more as 1 cpu to speed it up!
>
>>Maybe you misunderstood me because you thought that program X is not a constant
>>program because X means a variable.
>>Maybe I should use the letter C to be more clear.
>
>If you talk about the same program which is going to get used to
>parallellize a search tree in an SMP way, so not in an assymmetric way,
>then you can look in some issues of ICCAJ and see a lot of different
>ways to parallellize the searchtree!
>
>I don't need to mention that parallellizing over networks is harder to
>generate a speedup as communications are more expensive, as that's very
>obvious.
>
>The vaste majority of all computers at www.top500.org are going to be
>slower as a 16 processor alpha with shared memory for sure, despite that
>the first few machines each costed several billion US$ to build.
>
>The bandwidth on those machines is huge, so definitely there are going
>to be algorithms that speed you up a lot after very hard work.
>
>You can of course also run parallel over the internet, but sometimes it
>takes for me 10 minutes to just get connected to the internet.

I thought about running parralel over the internet.
>
>If my program would be part of a crucial search tree, then obviously
>sometimes you have 15 minutes delay for just a small part of the
>search tree if you would want to wait 15 minutes for answer.
>
>The more costly communication is the smaller the speedup in general,
>but in case of using internet connections the biggest problem isn't
>even communication SPEED. It is the uncertainty of the communication
>and the length of timeouts.
>
>How many plies must i let a program search? If i give each program 10 ply,
>what timeout do i give it to let it finish before giving someone
>else the same job? 1 minute? 2 minutes? Suppose this is a hard search tree
>and that no free node (remote machine in this case) is able to search
>the search tree in 2 minutes.

I think that every program should get a task to search for a fixed time and not
number of plies.

You start with a program that generate a tree of 1000 nodes when it takes a
short time(it may include the root position,all the positions 1 ply after the
root,a big part of the positions 2 plies after the root(not including positions
when a short search suggest that the line was illogical) and some extensions)


You give every computer to analyze one position for 3 minutes.
You get a score for every position and use the information of all the scores and
depthes to decide about the move.

You may send every position for 3 different computers if you are afraid you are
not going to get a response because of connections problems.

If the connection problems is on your side then it is a problem and you should
use a computer that usually does not have a connection problem.

Uri



This page took 0 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.