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

[Xen-devel] Time went backwards

  • To: "Xen Developers" <xen-devel@xxxxxxxxxxxxxxxxxxx>
  • From: "Niraj Tolia" <ntolia@xxxxxxxxx>
  • Date: Thu, 14 Feb 2008 16:18:26 -0800
  • Delivery-date: Thu, 14 Feb 2008 16:18:50 -0800
  • Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:mime-version:content-type:content-transfer-encoding:content-disposition; b=hWoiHjzzCOgw+2q0A9jBmxLM/HP60RE7eulSGkCKIRnxQFTxCpYmhSsvEWmvfZvB3p7kIv82MAwYHcxcUtixZ3B1TKskv/o3xKP60iHZg/c6HwEWTqTYCB0rt1VLEuA7j36yc4E1l+nRjdrxZ7twQtPVasN0XygGLAMKXz8rQgQ=
  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>


I have been experimenting with frequency scaling on a 4 core (2
sockets) AMD Opteron processors. The versions of Xen I have tested
with include xen-testing as well as xen-unstable (cs 17042). For both
these versions, I am using the linux 2.6.18-8 tree and have passed
cpufreq=dom0-kernel to the xen command line.

However, I get plenty of "Time went backwards" whenever I attempt to
change frequency. Does anyone know how this can be fixed?

% grep name /proc/cpuinfo | head -1
model name      : Dual-Core AMD Opteron(tm) Processor 2216 HE

powernow-k8: error - out of sync, fix 0x10 0x10, vid 0xe 0xc
powernow-k8: error - out of sync, fix 0x10 0x2, vid 0xc 0x12
Timer ISR/2: Time went backwards: delta=-20028937 delta_cpu=19939076
shadow=44550204818 off=949766763 processed=45520000000
 0: 45480000000
 1: 45520031987
 2: 45480031987
 3: 45490031987
Timer ISR/3: Time went backwards: delta=-19936433 delta_cpu=20031580
shadow=44552171478 off=957893422 processed=45530000000
 0: 45480000000
 1: 45520031987
 2: 45490031987
 3: 45490031987
Timer ISR/0: Time went backwards: delta=-19953088 delta_cpu=30046912
shadow=45494036645 off=16011896 processed=45530000000
 0: 45480000000
 1: 45520031987
 2: 45490031987
 3: 45500031987

(lots more Time went backwards messages follow these)


Xen-devel mailing list



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