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Cc: Peter Jeremy <peterjeremy@optushome.com.au>, freebsd-current@freebsd.org,
	Brian Candler <B.Candler@pobox.com>
Subject: Re: vmstat's entries type
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>From Julian Elischer <julian@elischer.org>, Mon, Jul 31, 2006 at 12:12:52PM -0700:
> but you do want to disable interrupts so that you don't get switched to 
> another cpu in the middle of it.
> That would result in the possibility of 2 threads writing to the same 
> stats at the same time.
Or just setup the sched to pin the kernel thread to the CPU and then 
use N_CPU threads for your packet processing + a load balancing algorithm
to allocate flows between threads.

I'm not saying this always the best solution, but certainly it is worth
consideration--especially in cases where the word 'flow' can be omitted
from my earlier statement without making anyone quesy.

(Parallelism versus pipelining: the difference between 
 Time-Division-Multiplexing each step in a packet's lifetime and 
 Spacial-Division Multiplexing the flows

 versus

 Time-Division-Multiplexing the flows and Spacial-Division
 Multiplexing the packet's lifetime.