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Subject: Re: The Stats just don't add up......

Author: Robert Hyatt

Date: 04:35:47 02/23/05

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On February 22, 2005 at 21:47:06, Bryan Hofmann wrote:

>On February 21, 2005 at 23:45:20, Robert Hyatt wrote:
>
>>On February 21, 2005 at 21:08:05, Bryan Hofmann wrote:
>>
>>>On February 20, 2005 at 19:56:51, Peter Skinner wrote:
>>>
>>>>On February 20, 2005 at 14:48:24, mike schoonover wrote:
>>>>
>>>>>hi all,
>>>>>been noticing this problem for a while with crafty.
>>>>>exits in ics mode quite freaquently.
>>>>>more with the newer ones.
>>>>>see:http://wbforum.volker-pittlik.name/viewtopic.php?t=1680
>>>>>it is not compile pessific.
>>>>>just wondering,is this a crafty or wb problem.
>>>>>help appreciated.
>>>>>regards
>>>>>mike
>>>>
>>>>I read your post on the wb forums, and the replies by Bryan Hoffman.
>>>>
>>>>I decided to test his version vs mine on the same computer, as I haven't done it
>>>>in a while.  Here are the results:
>>>>--------------------------------------------------------------------------------
>>>>unable to open book file [./book.bin].
>>>>book is disabled
>>>>unable to open book file [./books.bin].
>>>>hash table memory =   24M bytes.
>>>>pawn hash table memory =    6M bytes.
>>>>
>>>>Crafty v19.19 BH
>>>>
>>>>White(1): bench
>>>>Running benchmark. . .
>>>>......
>>>>Total nodes: 89729038
>>>>Raw nodes per second: 766914
>>>>Total elapsed time: 117
>>>>SMP time-to-ply measurement: 5.470085
>>>>White(1):
>>>>
>>>>EPD Kit revision date: 1996.04.21
>>>>unable to open book file [./book.bin].
>>>>book is disabled
>>>>unable to open book file [./books.bin].
>>>>hash table memory =   24M bytes.
>>>>pawn hash table memory =    6M bytes.
>>>>
>>>>Crafty v19.19 (1 cpus)
>>>>
>>>>White(1): bench
>>>>Running benchmark. . .
>>>>......
>>>>Total nodes: 89729038
>>>>Raw nodes per second: 787096
>>>>Total elapsed time: 114
>>>>SMP time-to-ply measurement: 5.614035
>>>>White(1):
>>>>-------------------------------------------------------------------------------
>>>>
>>>>Mine still seems slightly faster, and is the default compile with VC++ 2005
>>>>Express.
>>>>
>>>>Using these options:
>>>>
>>>>cl /Ox /O2 /GL /Gs /GA /GF /GT /Gr /MT /w /DNT_i386 /DWIN32 /D_CONSOLE /DWINDOWS
>>>>/DFAST /DEGTB6 /DEPD /DFUTILITY /DVC_INLINE_ASM crafty.obj egtb.obj
>>>>
>>>>Peter
>>>
>>>I find this hard to believe as I just ran your compile vs my compile on two
>>>different systems and Intel Pentium 4 2.8 GHz and a AMD 3000+ XP system. I'm
>>>using the full VC 2005 with POGO. The largest difference is in the AMD and I
>>>sure this is due to the POGO is being done on the AMD system.
>>>
>>>
>>>AMD 3000+ XP
>>>
>>>Skinners
>>>Crafty v19.19
>>>
>>>White(1): ben
>>>Running benchmark. . .
>>>......
>>>Total nodes: 96761642
>>>Raw nodes per second: 1256644
>>>Total elapsed time: 77
>>>SMP time-to-ply measurement: 8.311688
>>>White(1): quit
>>>
>>>Crafty v19.19 BH
>>>
>>>White(1): ben
>>>Running benchmark. . .
>>>......
>>>Total nodes: 96761642
>>>Raw nodes per second: 1362840
>>>Total elapsed time: 71
>>>SMP time-to-ply measurement: 9.014085
>>>
>>>
>>>
>>>
>>>Pentium 4 2.8GHz
>>>
>>>Skinners
>>>EPD Kit revision date: 1996.04.21
>>>unable to open book file [./book.bin].
>>>book is disabled
>>>unable to open book file [./books.bin]
>>>
>>>Crafty v19.19
>>>
>>>White(1): ben
>>>Running benchmark. . .
>>>......
>>>Total nodes: 96761642
>>>Raw nodes per second: 1018543
>>>Total elapsed time: 95
>>>SMP time-to-ply measurement: 6.736842
>>>White(1): quit
>>>
>>>Mine
>>>unable to open book file [./book.bin].
>>>book is disabled
>>>unable to open book file [./books.bin]
>>>
>>>Crafty v19.19 BH
>>>
>>>White(1): ben
>>>Running benchmark. . .
>>>......
>>>Total nodes: 96761642
>>>Raw nodes per second: 1063314
>>>Total elapsed time: 91
>>>SMP time-to-ply measurement: 7.032967
>>>White(1):
>>
>>
>>Hate to tell you guys, but you are all pissin' in the wind.  :)
>
>Doubtful but you are allowed to have your view.
>>
>>optimizations change from one processor to another, and I am not just talking
>>about AMD vs Intel.  Different memory timing, different cache size/timing,
>>different memory latency, different processor timings, the list goes on and on,
>>and each can affect the speed of the program sporadically and unpredictably.
>>Even poor memory/cache aliasing can make the same executable vary in speed
>>significantly from one day to the next on the same processor.
>>
>>Benchmarking and optimizing is not a "compile one time, run one test, and look
>>at the results".  It is a "compile once, run a bunch of tests, then clear memory
>>and run the same thing again.  Multiple times...  Whether you average or use the
>>best/worst/typical result is up to you, but there are too many variables for one
>>person to compile and think "this is the best there is".  There are even
>>compiler and optimizer differences to contend with beyond hardware difference...
>
>This is exactly what I have done time and time again with my compiles. I take it
>a step futher in that I have forced inlined some functions to attain a quicker
>compile and tested and both Intel and AMD platforms and had others test the
>compiles. All have pointed to one thing, the compiles I produce are faster then
>any of the others out there on a windows platform.

You can only make that claim for the specific machines you have tested on.  That
was my point.  If you haven't seen the memory/cache aliasing problem show up,
you have just been lucky.  It is there...



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