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Subject: Re: "3.1 comes from running a large number of positions several years ba

Author: Mikael Bäckman

Date: 04:03:55 05/07/04

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On May 07, 2004 at 04:30:09, Vincent Diepeveen wrote:

>On May 06, 2004 at 12:45:43, Robert Hyatt wrote:
>
>Bob let's get realistic.
>
>BK is a flawed testset to test parallel speedups at.

Why? I know nothing of parallel processing, but what in the BK makes it bad for
parallel testing?

/Mikael



>
>What happened is. You took 4 positions from that to 'proof' your 3.1.
>
>That gets disproven then by GCP doing statistical math where you know really
>less than a waterbird from. You do not even realize what the +- behind every
>measured speedup means. In fact you never provide them yourself.
>
>GCP then is doing different tests at your quads and very clearly determines 2.8
>using a-symmetric king safety.
>
>My 1.0 out of 2 speedup for crafty came of course from using tests with
>symmetric king safety.
>
>But GCP using 30 positions gets down to 2.8 speedup.
>
>And he gets one time 3.2 and another time 3.0 for speedup when searching
>fullwidth.
>
>a) this shows how poor your way of representing things is. You are just showing
>things like you want them to see
>
>b) i do not believe a crap you did a honest test where at position 21 in BK the
>crafty on average gets a 2.4 speedup when searching fullwidth. No matter how i
>test fullwidth at position 21, speedups are better there for fullwidth using
>asymmetric king safety.
>
>You did not do a honest testing to get to your numbers, even in those 4
>positions and yet you deny GCP's testing at 30 positions which were honestly
>done, to be true.
>
>This shows your true nature.
>
>
>
>>On May 06, 2004 at 12:19:13, Gian-Carlo Pascutto wrote:
>>
>>>I hope you don't mean the ones blow.
>>>
>>>Are you still claiming you 'measured' 3.1 which supposedly contradicts
>>>the 2.8 I measured?
>>
>>I don't know what any of that refers to.  My formula came from running the BK
>>test (23 positions, excluding #1 an instant mate in 3).
>>
>>I am trying to get the disk set up and installed now that I sent to AMD for the
>>last CCT event.  While I had access, I ran the BK test to get the data.  I had
>>promised Martin that I would post the numbers.
>>
>>But you _really_ need a better vocabulary.  I have not tried to "contradict
>>2.8".  I have _clearly_ said that the speedup varies and that 3.1 is the value
>>suggested by a linear approximation fit to a non-linear function.
>>
>>I do _not_ understand the obsession with "is it 2.8 or 3.1"?  It could well be
>>_both_.
>>
>>I have _always_ called this an approximation.  Let me get the log files and grep
>>the times for Martin.  I'll put the logs on my ftp machine since they will be
>>fairly long, if you want to see the opteron data for 1-4.
>>
>>>
>>>>Return-Path: <gcp@sjeng.org>
>>>>X-XS4ALL-To: <diep@maildrop.xs4all.nl>
>>>>Date: Fri, 9 Aug 2002 09:14:59 +0200 (MEST)
>>>>From: Gian-Carlo Pascutto <gcp@sjeng.org>
>>>>X-Sender:  <giancarlo@garf.natrese.be>
>>>>To: "Robert M. Hyatt" <hyatt@cis.uab.edu>
>>>>Cc: <diep@xs4all.nl>
>>>>Subject: Re: Parallel results so far
>>>>
>>>>
>>>>
>>>>On Thu, 8 Aug 2002, Robert M. Hyatt wrote:
>>>>
>>>>> Here is the results:
>>>>>
>>>>> -----------------------------------------------
>>>>>            ---null=2/3---        ---null=off---
>>>>> position   1cpu  4cpu S/U        1cpu  4cpu S/U
>>>>> kopec 21   27.9  10.7 2.6        30.3  12.4 2.4
>>>>> kopec 22   22.5   6.1 3.8        26.0   7.5 3.5
>>>>> kopec 23   33.5  11.2 3.0        20.9   6.4 3.3
>>>>> kopec 24   18.1   6.0 3.0        26.2   8.3 3.1
>>>>>
>>>>> -----------------------------------------------
>>>>> note.  all positions were searched for 30-45 seconds
>>>>> with the last 1-cpu output used to measure how long
>>>>> the 4-cpu search took to reach the same output (say
>>>>> the end of a search, or a PV move and score displayed).
>>>>>
>>>>> Vincent claimed "I never ran this test."  Thought I would
>>>>> run it _again_ just to expose "baloney".
>>>>>
>>>>> I think the conclusion from the above is
>>>>
>>>>Conlusions from the above? Howso?
>>>>
>>>>                speedup
>>>>Nullmove          3.1      +- 0.25
>>>>Non-nullmove      3.1      +- 0.25
>>>>
>>>>The standard errors (1SD) are way too huge to allow what
>>>>you try to conclude. I measured a speedup of 2.85 with
>>>>nullmove and 3.1 without, whereas your test wouldn't even
>>>>be able to differentiate between the two.
>>>>
>>>>If you want to scientifically settle this,
>>>>you'll need more and better data.
>>>>
>>>>(I couldn't find the CCC article reffered to earlier)
>>>>
>>>>--
>>>>GCP



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