Date: Tue, 16 Aug 2011 00:00:32 +0300 From: Alexander Motin <mav@FreeBSD.org> To: Joe Schaefer <joesuf4@gmail.com> Cc: hackers@freebsd.org Subject: Re: Clock stalls on Sabertooth 990FX Message-ID: <4E4988F0.7060000@FreeBSD.org> In-Reply-To: <CAOzHqcK3HMY=-7iNX05W43B=W5NP_bDWcJdDZ%2BEXk_Z%2BAdfAOw@mail.gmail.com> References: <CAOzHqcJMWrO1Q-v8WpzxnyB0-TMQvVaBC9WQ6Qf_CkK_FtT3VA@mail.gmail.com> <mailpost.1313435952.4224912.75598.mailing.freebsd.hackers@FreeBSD.cs.nctu.edu.tw> <4E498326.2060308@FreeBSD.org> <CAOzHqcK3HMY=-7iNX05W43B=W5NP_bDWcJdDZ%2BEXk_Z%2BAdfAOw@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 15.08.2011 23:57, Joe Schaefer wrote: > On Mon, Aug 15, 2011 at 4:35 PM, Alexander Motin<mav@freebsd.org> wrote: >> On 15.08.2011 22:18, Joe Schaefer wrote: >>> >>> On Mon, Aug 15, 2011 at 9:31 AM, Joe Schaefer<joesuf4@gmail.com> wrote: >>>> >>>> On Mon, Aug 15, 2011 at 8:32 AM, Andriy Gapon<avg@freebsd.org> wrote: >>>>> >>>>> on 13/08/2011 20:16 Joe Schaefer said the following: >>>>>> >>>>>> Brand new machine with a Phenom II X6 1100T and under chronic load >>>>>> the clock will stop running periodically until the machine eventually >>>>>> completely >>>>>> freezes. Note: during these stalls the kernel is still running, the >>>>>> machine is still >>>>>> mostly responsive, it's just that the clock is frozen in time. >>>>>> >>>>>> I've disabled Turbo mode in the bios and toyed with just about every >>>>>> other setting but nothing seems to resolve this problem. Based on the >>>>>> behavior >>>>>> of the machine (just making buildworld will eventually kill it, upping >>>>>> the -j flag >>>>>> just kills it faster), I'm guessing it has something to do with the >>>>>> Digi+ VRM features >>>>>> but again nothing I've tried modifying in the bios seems to help. >>>>>> >>>>>> I've tried both 8.2-RELEASE and FreeBSD 9 (head). Running head now >>>>>> with >>>>>> a dtrace enabled kernel. >>>>>> >>>>>> Suggestions? >>>>> >>>>> On head, start with checking what source is used for driving clocks: >>>>> sysctl kern.eventtimer >>>> >>>> % sysctl kern.eventtimer [master] >>>> kern.eventtimer.choice: HPET(450) HPET1(450) HPET2(450) LAPIC(400) >>>> i8254(100) RTC(0) >>>> kern.eventtimer.et.LAPIC.flags: 15 >>>> kern.eventtimer.et.LAPIC.frequency: 0 >>>> kern.eventtimer.et.LAPIC.quality: 400 >>>> kern.eventtimer.et.HPET.flags: 3 >>>> kern.eventtimer.et.HPET.frequency: 14318180 >>>> kern.eventtimer.et.HPET.quality: 450 >>>> kern.eventtimer.et.HPET1.flags: 3 >>>> kern.eventtimer.et.HPET1.frequency: 14318180 >>>> kern.eventtimer.et.HPET1.quality: 450 >>>> kern.eventtimer.et.HPET2.flags: 3 >>>> kern.eventtimer.et.HPET2.frequency: 14318180 >>>> kern.eventtimer.et.HPET2.quality: 450 >>>> kern.eventtimer.et.i8254.flags: 1 >>>> kern.eventtimer.et.i8254.frequency: 1193182 >>>> kern.eventtimer.et.i8254.quality: 100 >>>> kern.eventtimer.et.RTC.flags: 17 >>>> kern.eventtimer.et.RTC.frequency: 32768 >>>> kern.eventtimer.et.RTC.quality: 0 >>>> kern.eventtimer.periodic: 0 >>>> kern.eventtimer.timer: HPET >>> >>> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >>> Changing this to "i8254" seems to have resolved the stalls. >>> I'm running buildworld -j12 without issue. More than willing >>> to test out a patch or two against head if anyone's still >>> interested, otherwise I've thrown the change into loader.conf >>> and will move along quietly. >> >> 8.2-RELEASE you've mentioned doesn't have event timers subsystem and HPET >> timer driver. That makes me think it is strange at least. Can you try also >> LAPIC timer and do alike experiments with kern.timeocunter? > > My problems with 8.2-RELEASE may have been network based. I don't recall > precisely if the clock was stalling there, my guess is no based on > what you wrote. > > I'll test LAPIC next ... so far so good. Just so I'm clear, you'd > like me to tweak > kern.timecounter.hardware as well? (Currently it's HPET). Yes. Instead. Ticking clock depends on both timecounter and eventtimer. >> Also, please check whether kern.timecounter.tc.X.counter value changes for >> the selected timercounter and whether you are receiving timer interrupts in >> `vmstat -i` -- Alexander Motin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4E4988F0.7060000>