Re: AMD X2 unsynced TSC fix?

["Siddha, Suresh B" <suresh.b.siddha@intel.com>]

On Wed, Nov 01, 2006 at 01:46:48AM +0000, Sergio Monteiro Basto wrote:
> On Mon, 2006-10-30 at 18:41 -0800, Siddha, Suresh B wrote:
> > On Tue, Oct 31, 2006 at 12:03:28AM +0000, Sergio Monteiro Basto wrote:
> > > time.c: Lost 300 timer tick(s)! rip mwait_idle+0x33/0x4f)
> > > time.c: Lost 300 timer tick(s)! rip mwait_idle+0x33/0x4f)
> > > time.c: Lost 300 timer tick(s)! rip mwait_idle+0x33/0x4f)
> > > time.c: Lost 300 timer tick(s)! rip mwait_idle+0x33/0x4f)
> > 
> > Is this the reason why you are saying your system has unsynchronized TSC?
> > Some where in this thread, you mentioned that Lost ticks happen even
> > when you use  "notsc"
> > 
> > This sounds to me as a different problem. Can you send us the output
> > of /proc/interrupts?
> 
> /proc/interrupts on kernel 2.6.18
> http://bugzilla.kernel.org/attachment.cgi?id=9384&action=view
> dmesg w/o notsc kernel 2.6.19-rc4
> http://bugzilla.kernel.org/attachment.cgi?id=9385&action=view
> /proc/interrupts kernel 2.6.19-rc4 
> http://bugzilla.kernel.org/attachment.cgi?id=9386&action=view
> dmesg w/ notsc kernel 2.6.19-rc4 
> http://bugzilla.kernel.org/attachment.cgi?id=9387&action=view
> /proc/interrupts kernel 2.6.19-rc4
> http://bugzilla.kernel.org/attachment.cgi?id=9388&action=view
> list of interrupts give by windows XP
> http://bugzilla.kernel.org/attachment.cgi?id=9389&action=view

First of all, from "lost timer ticks" messages and the fact that "notsc"
decreases the number of ticks lost can't be concluded as a TSC sync issue.

Some device is hogging interrupts which results in lost timer ticks and from
your 2.6.18 interrupts info, usb seems to be the culprit.. It is probably
a side effect that "notsc" decreases the lost timer ticks..

copied Len who seems to be the owner of the bug for his thoughts..
(http://bugzilla.kernel.org/show_bug.cgi?id=6419) 

thanks,
suresh