Date: Mon, 8 Nov 2004 13:09:05 -0500 From: John Baldwin <jhb@FreeBSD.org> To: Pascal Hofstee <caelian@gmail.com> Cc: cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/kern sched_ule.c Message-ID: <200411081309.05747.jhb@FreeBSD.org> In-Reply-To: <d8a0b76204110519223860ef33@mail.gmail.com> References: <200410300735.i9U7ZrL2031884@repoman.freebsd.org> <d8a0b76204110519223860ef33@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Friday 05 November 2004 10:22 pm, Pascal Hofstee wrote: > On Sat, 30 Oct 2004 07:35:53 +0000 (UTC), Jeff Roberson > > <jeff@freebsd.org> wrote: > > jeff 2004-10-30 07:35:53 UTC > > > > FreeBSD src repository > > > > Modified files: > > sys/kern sched_ule.c > > Log: > > - In sched_prio() check to see if the kse is assigned to a runq as the > > check for TD_ON_RUNQ() no longer means the thread is really on a > > run- queue. I suspect this state should be re-evaluated as it must mean > > something else now. This fixes ULE+KSE+PREEMPTION on UP x86. > > Hi Jeff, > > I decided to take this commit as a good moment to give SCHED_ULE + > PREEMPTION a shot again in the hope of triggering potential bugs to > further improve SCHED_ULE. And i must say ... without > INVARIANTS/WITNESS ... SCED_ULE + PREEMPTION == SOLID ... No Panics > for well over 2 days during general desktop usage and compilation. > > I then decided to give it a real stress-test and decided to also > enable WITNESS, INVARIANTS and FULL_PREEMPTION. This combination > seemed just as stable at first ... untill i decided to shutdown > Firefox .. which caused a system panic with the famous "Negative nice > count" KASSERT from kern/sched_ule.c > > I did some additional testing and so far it seems that Every threaded > application seems to exhibit this panic upon exit. I don't have an > actual kerneldump at the moment ... but i should be able to generate > one and provide additional information and/or a backtrace if desired. > > To reproduce simply exit a multi-threaded application ... firefox, > ogg123 and apache-worker all caused the same panic. > > This is on a UP P2-400 MHz running 6.0-CURRENT as of November 3rd or 4th, I don't think multithreaded processes are ready for FULL_PREEMPTION yet on either scheduler, so I wouldn't use FULL_PREEMPTION for now. -- John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200411081309.05747.jhb>