On 7/27/07, Rafael Vanoni <[EMAIL PROTECTED]> wrote:
> It does sound a little black box, but if I'm not mistaken the idea was
> no to limit the number of user threads, despite the limited number of
> kernel threads. libthread decided which user thread would run and to
> which kernel thread they'd be assigned to. Allowing the existence of
> more user threads than kernel ones. So it makes sense to say that it
> scales well.

Also, when a thread yields in a M:N thread model, the userland
scheduler can pick another thread to run. On the other hand, a 1:1
system needs to get the kernel involved, and thus needs to cross the
user/kernel boundary.

There is still some performance advantage in M:N, but modern
processors are just so fast that the advantage is much smaller, but
handling signals in M:N is a bigger headache.

Rayson



>
> Rafael
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