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Subject: Re: tip for "simulating" an MP computer & performance of ABDADA

Author: Peter Kappler

Date: 19:23:48 05/28/00

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On May 28, 2000 at 20:43:18, Tom Kerrigan wrote:

>I found out that running multiple threads on one processor is not necessarily a
>good way to simulate an MP computer. You have to make sure each thread only
>searches one node per timeslice. If you're running Windows, you can do this by
>calling Sleep(0) once per node.
>
>I implemented Jean-Christophe Weill's ABDADA parallel search algorithm and I'm
>very happy with it. In terms of node counts, I get the following speedups when
>running BK:
>
>Threads     Speedup
>1           1
>2           1.81
>4           3.32
>8           5.66
>
>My implementation is pretty crude, so hopefully these numbers will improve over
>time. I'm not sure how this algorithm compares to others, but I like it for a
>few reasons:
>1) it's very easy to understand and implement
>2) it doesn't require any communication between threads, except for a fancy
>shared hash table
>3) if some threads barf, the search can still finish (this hasn't happened to me
>yet, but it's cool for peace of mind)
>
>-Tom



Looks interesting.  Where can I find more info?

--Peter




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