cvs commit: src/sys/kern kern_sig.c
davidxu at freebsd.org
Wed Mar 2 22:55:59 PST 2005
David Schultz wrote:
>On Thu, Mar 03, 2005, Mike Silbersack wrote:
>>On Thu, 3 Mar 2005, David Schultz wrote:
>>>Of course, there's another possible solution which is to remove
>>>the swapping code entirely. That would certainly simplify things,
>>>but it would also make FreeBSD degrade less gracefully under load.
>>I don't think that would be a big loss; by the time you're doing a lot of
>>process swapping, you're pretty screwed.
>>A process has to be swapped back in in order for it to be killed, right?
>>We might be better off without swapping, in that case.
>Yeah, with 16K kernel stacks, you'd have to swap a lot of threads
>to make a big difference in the amount of wired memory in the
>system. KSE helps with this, because processes with thousands of
>user threads don't have thousands of kernel threads.
This only happens at comparative idle time, if the process is a heavy
I/O bound process,
this does not help.
>Another thing that swapping does, though, is prevent some
>processes from running for a while when the system is under load,
>thereby reducing contention for resources and allowing the other
>processes to get things done. If people decide to go this way, it
>might be a good idea to keep the second feature. It costs very
>little in terms of complexity because no actual swapping is done.
>But who knows? Maybe nobody cares about this, either...
I would like to not swap out kernel stack, it allows me to write some
this is my personal favorit. :=)
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