From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Wed, 28 Oct 2009 14:32:46 -0500
From: Jack Norton <jack@0x6a.com>
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To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: Re: [9fans] parallel systems
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Sam Watkins wrote:
> I think my main points were good.
>
>   * can parallelize by duplicating subsystems / divide and conquer
>   * can parallelize by pipelining, even down to the arithmetic level
>   * latency is limited by Ahmdal's law, potential throughput should not be
>   * multi-tasking can potentially use close to the full power of a system
>
> A factory is a parallel system.  A car factory can come close to fully
> utilizing thousands of human and robot workers.
>
> I think well-designed parallel systems can efficiently solve many laborious
> computing problems.  Invocations of Ahmdal have not convinced me otherwise.
>
> Sam
>
>
I would say a factory is heavily pipelined.  Although if the jobs aren't
big enough, the workers are underutilized.  The mediators (supervisors)
that keep said workers efficiently running are paid more than the
workers, and it can be deduced that their job is more critical
overall.   Hmm what does that say about parallel computer systems?
Maybe you should have a shop foreman design a parallel system.   I
thought I would respond as I work at a small company and we build all
our parts in our factory.  I regularly deal with such parallel system
latencies...

also, one more thought: near 100% factory utilization only occurs when
the assembly steps (pipeline) and division of assembly (divide and
conquer) is tailored for the exact product (task/instruction/process) to
be made.  There is no such thing as a 100% utilized general purpose
factory.  At least not from what I have seen.

-Jack