Subject: Re: So I'll bite. M:N w/o SA - how?
To: None <firstname.lastname@example.org>
From: Bucky Katz <email@example.com>
Date: 02/22/2007 10:42:51
Joerg Sonnenberger <firstname.lastname@example.org> writes:
> On Wed, Feb 21, 2007 at 11:40:24AM -0800, Bucky Katz wrote:
>> Bill Studenmund <email@example.com> writes:
>> > When a thread blocks in the kernel, you'd like to run something
>> > else on that thread, no?
>> Yes. This is why I don't believe you can accomplish this entirely
>> in userland.
> That's the point where I disagree. I do not think it is necessary to do
> that or even helpful. Let blocking events block the lwp. When you took
> the time for a trap, the context switching overhead is reasonably small.
In the uniprocessor case M:N degenerates to N:1, in practice. If I let
the 1 lwp block, how do I get any of the other threads scheduled?