Date: Sat, 28 Oct 2006 12:55:56 +0800 From: David Xu <davidxu@freebsd.org> To: freebsd-current@freebsd.org Cc: Daniel Eischen <deischen@freebsd.org>, Paul Allen <nospam@ugcs.caltech.edu>, Julian Elischer <julian@elischer.org>, "Alexandre \"Sunny\" Kovalenko" <Alex.Kovalenko@verizon.net>, current@freebsd.org Subject: Re: Comments on the KSE option Message-ID: <200610281255.57135.davidxu@freebsd.org> In-Reply-To: <4542DE59.5010500@elischer.org> References: <45425D92.8060205@elischer.org> <200610281206.13588.davidxu@freebsd.org> <4542DE59.5010500@elischer.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Saturday 28 October 2006 12:36, Julian Elischer wrote: > >> Julian > > > > As you are emphasizing fairness, I must say I don't believe fairness in > > libpthread either, > > you mean you don't think it is a good idea or that you don't think it > works? (sorry, I know that your english is way better than my > chinese ;-) > I meant I don't think libpthread's userland scheduler + ksegrp in kernel has implemented fairness between threads correctly. > > I don't think writing a fairness scheduler is an > > easy work, does kernel have made fairness for threads in same ksegrp, > > so does libpthread's userland scheduler ? > > The kernel is only responsible for making sure that one ksegrp > (usually a process in my original idea) is not unfair to another > ksegrp. > What happens within the ksegrp is not it's interest. And no it > isn't an easy thing to do which is why I had hoped that some > PhD student would have taken it up by now :-) > > > they don't, it can make threads > > in same ksegrp misbehaviored, so what we have done is still process > > scheduling fairness even there is ksegrp in kernel, and now sacrificed > > fairness between threads. > > once again, I'm not sure what you mean by that. >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200610281255.57135.davidxu>