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Date: Thu, 08 May 2008 15:27:44 -0700
From: Julian Elischer <julian@elischer.org>
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To: "Murty, Ravi" <ravi.murty@intel.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: SW_PREEMPT and cpu runq
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Murty, Ravi wrote:
> Hi,
> 
>  
> 
> When a thread is being switched out and it is being preempted (e.g. time
> quantum expires), why does sched_switch hold it on the current cpu? i.e.
> why does the code see that it was preempted and put it back on the same
> queue?
> 
> In other cases it looks to see if it can be migrated and the thread goes
> back some place else. If a thread is being kicked out and there is a
> perfectly idle CPU some where on the system, wouldn't it make sense to
> migrate the thread?

it shouldn't be held..
why do you think it is?
(and is this in 6.x still?)

> 
>  
> 
> Thanks
> Ravi
> 
>  
> 
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