[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Xen 4 TSC problems



On 9/17/2011 12:40 AM, Jeremy Fitzhardinge wrote:
On 09/15/2011 11:03 PM, Philippe.Simonet@xxxxxxxxxxxx wrote:
-----Original Message-----
From: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx [mailto:xen-devel-
bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of Jeremy Fitzhardinge
Sent: Thursday, September 15, 2011 6:25 PM
To: Konrad Rzeszutek Wilk
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx; Philippe Simonet
Subject: Re: [Xen-devel] Xen 4 TSC problems

On 09/15/2011 01:24 AM, Konrad Rzeszutek Wilk wrote:
On Tue, Sep 13, 2011 at 09:16:27AM +0200, Philippe Simonet wrote:
Hi Xen developers
Lets try this again, this time Cc-ing Jeremy.
i just would like to inform you that I have exactly the same problem
with Debian squeeze and xen, with
50 seconds time jump on my dom0 and domu. NTP is running on all
dom0/domuU, clocksource is 'xen'
everywhere.

some messages :
syslog :
Sep 11 13:56:50 dnsit22 kernel: [571603.359863] Clocksource tsc
unstable (delta = -2999662111513 ns)

xm dmesg :
...
(XEN) Platform timer is 14.318MHz HPET ...
(XEN) Platform timer appears to have unexpectedly wrapped 10 or more
times.
(XEN) TSC marked as reliable, warp = 0 (count=2) ...

I had some contact with Olivier Hanesse and it indicates that he
doesn't have any solution for this problem, and all what was proposed
in February didn't solved this problem.
That looks like Xen itself is having problems keeping track of time.  If it 
can't
manage it, then there's not much the guest kernels can do about it.

Which was the max_cstate=0 ?
..
config :
--------------------------------------
Linux dnsit22.swissptt.ch 2.6.32-5-xen-amd64 #1 SMP Tue Jun 14
12:46:30 UTC 2011 x86_64 GNU/Linux
--------------------------------------
HP DL385
--------------------------------------
vendor_id       : AuthenticAMD
cpu family      : 16
model           : 9
model name      : AMD Opteron(tm) Processor 6174
stepping        : 1
cpu MHz         : 3058776.574
OK, that is really messed up. Your house must be on fire for the
machine to be running at 3058GHz!

Jeremy, this sounds familiar - did we have a patch for this in your
2.6.32 tree?
Not that I can think of.  All I can suggest from the kernel side is that perhaps
some of the ACPI power stuff isn't being set up properly, and that makes the
CPU do very strange things with its TSC/power states in general.

how can i detect that ?

the /proc/acpi/processor path is empty,

find /proc/acpi
  /proc/acpi
  /proc/acpi/processor
  /proc/acpi/button
  /proc/acpi/button/power
  /proc/acpi/button/power/PWRF
  /proc/acpi/button/power/PWRF/info
  /proc/acpi/thermal_zone
  /proc/acpi/wakeup
  /proc/acpi/sleep
  /proc/acpi/fadt
  /proc/acpi/dsdt
  /proc/acpi/info
  /proc/acpi/power_resource
  /proc/acpi/embedded_controller

dmesg | grep -I acpi
  [    1.205647] hpet_acpi_add: no address or irqs in _CRS

lsmod | grep -i acpi
  acpi_processor          5087  1 processor,[permanent]
What does "xenpm start 5" say?

     J


here it is :

root@xxxxxxxxxxxxxxxxxxx ~# xenpm start 5
Timeout set to 5 seconds
Start sampling, waiting for CTRL-C or SIGINT or SIGALARM signal ...
Elapsed time (ms): 5028

CPU0:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU1:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU2:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU3:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU4:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU5:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU6:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU7:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU8:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU9:   Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU10:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU11:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU12:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU13:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU14:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU15:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU16:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU17:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU18:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU19:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU20:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU21:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU22:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz

CPU23:  Residency(ms)           Avg Res(ms)
  Avg freq      18      KHz






_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.