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Subject: Re: The need to unmake move

Author: Tony Werten

Date: 01:54:53 09/04/03

Go up one level in this thread


On September 03, 2003 at 10:44:11, Sune Fischer wrote:

>On September 03, 2003 at 10:35:11, Gian-Carlo Pascutto wrote:
>
>>On September 03, 2003 at 10:26:19, Sune Fischer wrote:
>>
>>>>What is your point?
>>>
>>>Heh :)
>>>
>>>You said (remote) checking for fail_high conditions at every node was required,
>>>and I disagree.
>>
>>I never say 'at every node'.
>
>You said constantly, then I don't know what you mean by that.
>
>>Each time you get a subtree score, you must send out the score update to
>>all processors, or store it locally and rely on remote processors to check
>>it in your memory.
>>
>>Either way, you need remote accesses.
>>
>>Got it now?
>
>This is an entirely different matter, you don't get subtree scores "constantly".
>
>And I still say you only have to access when there is something to communicate.
>
>If you just quietly exit the subtree on a fail low, I see no need for
>communication.

I suddenly see the point you're missing. What you describe works correct on a
dual machine only.

Think about a 4 processor machine.

processor 1 and 2 are running.

processor 3 runs and starts a new thread on proc. 4

Now proc 4 is done, proc 3 get's this (ie he get's a done message, with score )

But how are proc 1 and 2 going to know that 4 is available ?

Tony

>
>-S.
>>--
>>GCP



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