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Date: Sun, 06 Mar 2005 11:21:46 +0800
From: David Xu <davidxu@freebsd.org>
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To: Sam Lawrance <boris@brooknet.com.au>
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cc: current@freebsd.org
Subject: Re: Swapped out procs not brought in immediately after child exits
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Sam Lawrance wrote:

>On Sun, 2005-03-06 at 09:43 +0800, David Xu wrote:
>  
>
>>Sam Lawrance wrote:
>>
>>    
>>
>>>>How-To-Repeat:
>>>>   
>>>>
>>>>        
>>>>
>>>Run a shell somewhere (first). Su or run another shell or similar (second).
>>>Wait until the first shell has swapped out (might require running some other
>>>memory hogs). Exit the second shell. Notice that the second shell takes a
>>>long time to exit.
>>>
>>> 
>>>
>>>      
>>>
>>This reminds me that it is another swappable kernel stack problem, if we 
>>don't have
>>it, we even needn't TDP_WAKEPROC0  hack, interesting. :)
>>    
>>
>
>Do I understand this correctly: When a process is swapped back in, the
>kernel stack is faulted in immediately and user space is faulted in as
>needed?
>
>And without swappable kernel stack, no extra action is required because
>the kernel stack is already in, and user space will be faulted in as
>usual?
>
>  
>
Yes, you are right.