On Wed, Apr 18, 2007 at 08:37:11AM +0200, Nick Piggin wrote: > I don't know how that supports your argument for unfairness,
I never had such an argument. I like fairness. My argument is that -you- don't have an argument for making fairness a -requirement-. > processes are special only because that's how we've always done > scheduling. I'm not precluding other groupings for fairness, though. If you make one form of fairness a -requirement- for all acceptable algorithms, your -are- precluding most other forms of fairness. If you refuse to define what "fairness" means when specifying your requirement, what's the point of requiring it? > What do you mean optimal? If your criteria is fairness, then of course > it is optimal. If your criteria is throughput, then it probably isn't. I don't know what optimal behavior is. And neither do you. It may or may not be fair. It very likely includes small deviations from fair. > > [2] It's trivial to construct two or more perfectly reasonable and > > desirable definitions of fairness that are mutually incompatible. > > Probably not if you use common sense, and in the context of a replacement > for the 2.6 scheduler. Ok, trivial example. You cannot allocate equal CPU time to processes/tasks and simultaneously allocate equal time to thread groups. Is it common sense that a heavily-threaded app should be able to get hugely more CPU than a well-written app? No. I don't want Joe's stupid Java app to make my compile crawl. On the other hand, if my heavily threaded app is, say, a voicemail server serving 30 customers, I probably want it to get 30x the CPU of my gzip job. -- Mathematics is the supreme nostalgia of our time. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
