Swapped out procs not brought in immediately after child exits
David Xu
davidxu at freebsd.org
Sat Mar 5 19:21:40 PST 2005
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.
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