Date: Tue, 26 Oct 2004 13:18:25 -0400 From: Stephan Uphoff <ups@tree.com> To: John Baldwin <jhb@FreeBSD.org> Cc: freebsd-current@FreeBSD.org Subject: Re: number of CPUs and IPI panic Message-ID: <1098811105.20390.16988.camel@palm.tree.com> In-Reply-To: <200410211705.45147.jhb@FreeBSD.org> References: <20041020221659.33824.qmail@web21124.mail.yahoo.com> <1098320716.20390.416.camel@palm.tree.com> <200410211705.45147.jhb@FreeBSD.org>
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On Thu, 2004-10-21 at 17:05, John Baldwin wrote: > On Wednesday 20 October 2004 09:05 pm, Stephan Uphoff wrote: > > Can you try the attached patch? > > ( Hope it still applies since it is a few weeks old) > > > > If this does not work I have a few more questions next week. > > Unfortunately it can enable interrupts with sched_lock held which can result > in deadlocks due to ithread preemption (IIRC, maybe not as badly with the > newer preemption code.) The code only enables interrupts for TLB shootdowns. In this case it is guaranteed that it holds the smp_ipi_mtx that as a side effect protects it against preemption and holds no other spin mutex. I don't see the problem. I am thinking about implementing the bitmap based stuff be talked about a few weeks ago to avoid having more than one queued IPI of the same type. > > > Stephan > > > > On Wed, 2004-10-20 at 18:16, Nik Azim Azam wrote: > > > sorry for not posting this information earlier. > > > > > > i'm running on SCHED_4BSD, with PREEMPTION. the same > > > panic occours without PREEMPTION. the kernel is > > > generic except that i've removed some devices that i > > > dont need. > > > > > > --- Gavin Atkinson <gavin.atkinson@ury.york.ac.uk> > > > > > > wrote: > > > > On Wed, 20 Oct 2004, Nik Azim Azam wrote: > > > > > hello list, > > > > > > > > > > i'm doing some testing on a 6 cpu pentium II > > > > > > > > overdrive > > > > > > > > > computer with 6-CURRENT. with 6 cpus, the system > > > > > > > > will > > > > > > > > > panic easily with moderate load (previous IPI is > > > > > stuck). i edited sys/i386/sys/param.h file and > > > > > > > > lowered > > > > > > > > > the MAXCPU to 4. now the system is running with 4 > > > > > > > > cpus > > > > > > > > > and it survived a make buildworld + portupgrade at > > > > > > > > the > > > > > > > > > same time. > > > > > > > > > > is this a known problem? i can give more > > > > > > > > information > > > > > > > > > if anyone interested. > > > > > > > > Are you using SCHED_ULE? (I believe it's the default > > > > in 6-CURRENT...) > > > > > > > > If so, try with SCHED_4BSD. ULE has known problems > > > > at the moment. > > > > > > > > Gavin > > > > > > _______________________________ > > > Do you Yahoo!? > > > Declare Yourself - Register online to vote today! > > > http://vote.yahoo.com > > > _______________________________________________ > > > freebsd-current@freebsd.org mailing list > > > http://lists.freebsd.org/mailman/listinfo/freebsd-current > > > To unsubscribe, send any mail to > > > "freebsd-current-unsubscribe@freebsd.org"
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