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Subject: Re: [rfc] bind per-cpu timeout threads to each CPU
From: Adrian Chadd <adrian@freebsd.org>
To: John Baldwin <jhb@freebsd.org>
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Cc: Alexander Motin <mav@freebsd.org>,
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On 20 February 2014 11:17, John Baldwin <jhb@freebsd.org> wrote:

> (A further variant of this would be to divorce cpu0's swi from the
> catch-all softclock and let the catch-all softclock float, but bind
> all the per-cpu swis)

I like this idea. If something (eg per-CPU TCP timers, if it's turned
on) makes a very specific decision about the CPU then it should be
fixed. Otherwise a lot of the underlying assumptions for things like
RSS just aren't guaranteed to hold.

It could also perhaps extend to some abstract pool of CPUs later, if
we wanted to do things like one flowing swi per socket or whatnot when
we start booting on 1024 core boxes...

-a