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Subject: Re: Generating endgame tablebases

Author: Michael Nieves

Date: 14:54:32 10/11/01

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You guys reminded of an "accident" I had in the early nineties working on a
Cray.

Our firm had contracted some CPU time on a Cray on an DOD facility.  I migrated
a version of scientific code to the cray to do some testing.  I fired off the
code and went to grab some coffee.

I returned 5 minutes later and observed that the program had hung.  I killed the
process and went back to our slow alphas to do some debugging.  Turned out to be
a simple bug that caused an infinite loop.

I didn't think much of it until a month later when I received a $10,000 bill
from the DOD.

Needless to say, I treaded carefully thereafter.

On October 11, 2001 at 11:23:38, Robert Hyatt wrote:

>On October 11, 2001 at 00:43:57, Slater Wold wrote:
>
>>On October 11, 2001 at 00:27:17, Robert Hyatt wrote:
>>
>>>On October 10, 2001 at 22:55:27, Slater Wold wrote:
>>>
>>>>On October 10, 2001 at 22:36:01, Robert Hyatt wrote:
>>>>
>>>>>On October 10, 2001 at 16:55:16, Olaf Jenkner wrote:
>>>>>
>>>>>>>Some took hours on a Cray (Stiller).  Figure months on a PC for those.
>>>>>>>No idea how long the really bad ones will take (kppkpp for example.)
>>>>>>>The promotion cases will certainly take a _long_ while...
>>>>>>
>>>>>>Didn't use Stiller the connection machine?
>>>>>>I remember that I read 1991 about this.
>>>>>>
>>>>>>OJe
>>>>>
>>>>>
>>>>>He used both.  Burton Wendroff/Tony Warnock got him some time on a C90
>>>>>sometime in the 1993 time frame...  The advantage of the C90 is that it
>>>>>comes with 32 gigabytes of RAM, which was helpful for making the generator
>>>>>run very fast...  Of course, he didn't do any compression, and he couldn't
>>>>>write the files out to anything for saving them...  but he did compute some
>>>>>statistics about them before chucking them.
>>>>
>>>>Any idea where to get those statistics Bob?
>>>
>>>
>>>I believe Lewis published some of them quite some while back.  But the
>>>thing he published was mainly "deepest mate" and the like.  I didn't follow
>>>this very closely, and only remember Wendroff asking for "my contact" up at
>>>Cray in trying to set the time up...
>>
>>Ok.  Thanks.
>>
>>>
>>>
>>>
>>>
>>>>
>>>>Who is compiling them now?
>>>
>>>Only Eugene so far as I know...
>>
>>On what?  And how is he doing the 6 pieces?  I thought you needed a 64-bit OS
>>and a LOT of memory and HD space.
>
>
>Last I heard he was using some "unused" alphas at microsoft.  Since MS
>no longer supports the alpha with NT, the machines were free and he
>grabbed them. :)
>
>
>
>>
>>>
>>>
>>>
>>>>
>>>>How hard is it to get time on a Cray?
>>>>
>>>
>>>Have you noticed a "lack" of "cray blitz"?  Draw your own conclusion.  :)
>>
>>Well, it was running at one time!  What's the difference between then and now!?!
>
>
>we could get time to play in one tournament a year.  Maybe a few nights of
>testing between 1am and 5am if we were lucky.
>
>
>
>
>>
>>>
>>>The machines sell for $60,000,000.00 or so.  So yes, it takes a lot of
>>>haggling to get time...
>>
>>Jeez....
>>
>>>
>>>At one time CPU time was going for $20,000 per hour...
>>
>>Man oh man.  I went looking up Cray's, (other than www.cray.com) and all I could
>>find was crap about Cray, Inc. suing the United States of America.  (The CIA was
>>one of the organizations involved.)
>>
>
>
>Not sure what that is about.  The US Government (the NSA and other "black"
>agencies as well) are their best customers.  NSA has a "cluster" of crays
>if you can call that a "cluster".  :)
>
>
>
>
>>So renting one for a day is pretty much outta the question for me.....as I don't
>>have $480,000 to blow.
>>
>>What a shame.
>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>>
>>>>
>>>>Slate



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