From: Jesper Krogh <jesper@krogh.cc>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Linux 2.6.29-rc6
Date: Thu, 26 Feb 2009 23:04:03 +0100 [thread overview]
Message-ID: <49A711D3.8070001@krogh.cc> (raw)
In-Reply-To: <alpine.LFD.2.00.0902262249390.9135@localhost.localdomain>
Thomas Gleixner wrote:
> On Thu, 26 Feb 2009, john stultz wrote:
>> On Thu, 2009-02-26 at 22:35 +0100, Jesper Krogh wrote:
>>> john stultz wrote:
>>>> On Thu, Feb 26, 2009 at 12:43 PM, Jesper Krogh <jesper@krogh.cc> wrote:
>>>>> Linus Torvalds wrote:
>>>>>> On Thu, 26 Feb 2009, Jesper Krogh wrote:
>>>>>>> 2.6.26.8 doesnt have this problem.
>>>>>>>
>>>>>>> The "current_clocsource" is the same on both systems.
>>>>>>>
>>>>>>> $ cat /sys/devices/system/clocksource/clocksource0/current_clocksource
>>>>>>> tsc
>>>>>> What does the frequency calibrate to? It should be in the dmesg. Does it
>>>>>> differ by a big amount?
>>>>> Non-working:
>>>>> $ dmesg | grep -i freq
>>>>> [ 0.004007] Calibrating delay loop (skipped), value calculated using
>>>>> timer frequency.. 4620.05 BogoMIPS (lpj=9240104)
>>>>>
>>>>> 2.6.26.8 doesn't have that information.
>>>> I'm surprised the clocksource watchdog isn't catching it.
>>>>
>>>> What's the output from:
>>>> cat /sys/devices/system/clocksource/clocksource0/available_clocksource
>>> $ cat /sys/devices/system/clocksource/clocksource0/available_clocksource
>>> tsc acpi_pm jiffies
>> Hmm. Does booting w/ "clocksourc=acpi_pm" also show the severe (~550ppm,
>> which NTP can't handle) drift?
>>
>> >From the dmesg, I don't see any major calibration difference right off.
>>
>> So I'd suspect something like TSC halting in idle could be causing
>> problems, but the watchdog should catch that as well. My only guess at
>> this point is that the ACPI PM is halting in idle along with the TSC.
>
> But why would it do that on 29-rc6 and not on 2.6.28.8 ? I'm not aware
> of changes which might cause that.
My comparison is 2.6.26.8 not 2.6.28.8 .. so fairly old.
It is a small cluster, so I'm slipping some test-kernels in when the
cluster is idle.
--
Jesper
next prev parent reply other threads:[~2009-02-26 22:04 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-02-23 4:31 Linux 2.6.29-rc6 Linus Torvalds
2009-02-23 14:07 ` Linux 2.6.29-rc6 - Fix oops in i915_gem_retire_requests Karsten Wiese
2009-02-26 11:15 ` Linux 2.6.29-rc6 Jesper Krogh
2009-02-26 17:17 ` MTD_CK804XROM warning (Was: Linux 2.6.29-rc6) Marcin Slusarz
2009-02-26 17:53 ` Linux 2.6.29-rc6 Linus Torvalds
2009-02-26 19:22 ` David Woodhouse
2009-02-26 19:31 ` Jesper Krogh
2009-02-26 19:36 ` David Woodhouse
2009-02-26 19:46 ` Jesper Krogh
2009-02-26 19:49 ` David Woodhouse
2009-02-26 20:53 ` Carl-Daniel Hailfinger
2009-02-26 20:32 ` Linus Torvalds
2009-02-26 19:55 ` Jesper Krogh
2009-02-26 20:33 ` Linus Torvalds
2009-02-26 20:43 ` Jesper Krogh
2009-02-26 21:19 ` john stultz
2009-02-26 21:35 ` Jesper Krogh
2009-02-26 21:46 ` john stultz
2009-02-26 21:54 ` Thomas Gleixner
2009-02-26 22:04 ` Jesper Krogh [this message]
2009-02-27 6:30 ` Jesper Krogh
2009-03-01 13:51 ` Jesper Krogh
2009-02-26 21:49 ` Linus Torvalds
2009-03-01 15:04 ` Jesper Krogh
2009-02-26 21:54 ` john stultz
2009-02-26 22:06 ` Thomas Gleixner
2009-02-26 22:24 ` Linus Torvalds
2009-02-26 22:31 ` Linus Torvalds
2009-02-26 22:31 ` john stultz
2009-02-26 22:40 ` Linus Torvalds
2009-02-26 22:59 ` john stultz
2009-02-27 7:33 ` Ingo Molnar
2009-02-27 20:50 ` john stultz
2009-02-27 6:47 ` Jesper Krogh
2009-02-27 20:35 ` john stultz
2009-03-01 20:13 ` Jesper Krogh
2009-03-02 9:53 ` Jesper Krogh
2009-03-02 21:27 ` john stultz
2009-03-03 6:04 ` Jesper Krogh
2009-03-03 19:53 ` john stultz
2009-03-03 20:19 ` Jesper Krogh
2009-03-03 22:22 ` john stultz
2009-03-04 15:30 ` Jesper Krogh
2009-03-04 18:36 ` Jesper Krogh
2009-03-04 18:57 ` John Stultz
2009-03-05 2:39 ` john stultz
2009-03-05 2:52 ` john stultz
2009-03-05 8:43 ` Ingo Molnar
2009-03-06 3:13 ` john stultz
2009-03-06 3:54 ` john stultz
2009-03-06 11:34 ` Ingo Molnar
2009-03-09 20:42 ` Jesper Krogh
2009-03-10 4:26 ` Linus Torvalds
2009-03-10 11:29 ` Thomas Gleixner
2009-03-10 19:42 ` Jesper Krogh
2009-03-10 22:22 ` Thomas Gleixner
2009-03-15 19:53 ` Jesper Krogh
2009-03-16 18:40 ` Jesper Krogh
2009-03-15 1:19 ` Linus Torvalds
2009-03-15 15:44 ` Jesper Krogh
2009-03-15 18:09 ` Linus Torvalds
2009-03-15 18:38 ` Jesper Krogh
2009-03-15 19:02 ` Linus Torvalds
2009-03-15 19:52 ` Jesper Krogh
2009-03-16 18:59 ` Jesper Krogh
2009-03-16 19:32 ` Linus Torvalds
2009-03-17 1:43 ` john stultz
2009-03-17 8:14 ` Ingo Molnar
2009-03-17 15:48 ` Linus Torvalds
2009-03-17 16:13 ` Ingo Molnar
2009-03-17 16:28 ` Linus Torvalds
2009-03-17 16:40 ` Ingo Molnar
2009-03-17 17:28 ` Olivier Galibert
2009-03-21 9:11 ` Jesper Krogh
2009-03-21 10:06 ` Ingo Molnar
2009-03-15 20:32 ` Linus Torvalds
2009-03-03 20:39 ` Jesper Krogh
2009-03-03 22:16 ` john stultz
2009-03-04 5:36 ` Jesper Krogh
2009-03-01 15:09 ` Jesper Krogh
2009-03-01 15:44 ` Linux 2.6.29-rc6 (clocksource) Sitsofe Wheeler
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