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Date: Sun,  2 Mar 2008 19:19:13 -0800
From: "ron minnich" <rminnich@gmail.com>
To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu>
Subject: Re: [9fans] GCC/G++: some stress testing
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On Sun, Mar 2, 2008 at 2:00 PM, Philippe Anel <xigh@free.fr> wrote:

>  If CSP system itself takes care about memory hierarchy and uses no
>  synchronisation (using IPI to send message to another core by example),
>  CSP scales very well.

Is this something you have measured or is this conjecture?

>  Of course IPI mechanism requires a switch to kernel mode which costs a
>  lot. But this is necessary only if the destination thread is running on
>  another core, and I don't think latency is very important in algorigthms
>  requiring a lot of cpus.

same question.

For a look at an interesting library that scaled well on a 1024-node
SMP at NASA Ame's, by Jim Taft.
Short form: use shared memory for IPC, not data sharing.

he's done very well this way.

ron