On Tue, May 16, 2017 at 09:10:53AM -0400, Steven Rostedt wrote: > On Tue, 16 May 2017 11:32:41 +0100 > Juri Lelli <juri.le...@arm.com> wrote: > > > > Not sure, but if we are going to retry a lot it might be better off to > > put proper locking instead? We could also simply bail out when we notice > > Actually, locking can make it much worse. I've been playing with RT on > boxes with 240 cores (with HT turned off!), and *any* locks in the > scheduler can cause huge contention.
OK. I give up patches adding locks here. Thank you for explaning why you did not write code in such a way like mine. > > that something is changed under our feet. I'd say (again :) we might > > first want to understand (with some numbers) how bad the problem is and > > then fix it. I guess numbers might also help us to better understand > > what the best fix is? > > Exactly. I haven't seen any numbers. Yes, it is not perfect, but we > don't know how unperfect it is. Numbers will help to know if there is > even a problem or not with the current solution. Yes. I am also curious about the number and want to check the number, but it's not easy to me since I don't have such a big machine. For now, only thing I can do is to skip the patch. Thank you very much for all of your opinions.
