Timer ISR/0: Time went backwards

Timer ISR/0: Time went backwards

[Ted Kaczmarek]

On Fri, 2005-10-07 at 10:03 -0400, Ted Kaczmarek wrote:
> ###############################################
> changeset:   7234:bd37123974b2
> Centos 4.1 dom0, Tyan 2462 SMP, 8k kernel stack
> ###############################################
> 
> 7 UP guests, have 1 very fat guest(1200 megs, running tomcat4,
> postgresql, and opennms unstable) domain1, issuing 
> xm save domain1;xm restore domain1
> 
> saw these log messages.
> 
> XEN) (file=grant_table.c, line=940) Grant unref rd(13) ld(0) frm(1a8cd)
> flgs(1).
> (XEN) (file=grant_table.c, line=940) Grant unref rd(13) ld(0) frm(1a614)
> flgs(1).
> 
> 
> DomU's exceeding 24 hours of uptime, other than issues related to load
> on dom0 things are behaving rather well.
> 
> Where can a user obtain docs on the grant tables by the way?
> Is the source the only present place?
> 
> 
> Regards
> Ted
> 
> 
> _______________________________________________
Within seconds of setting this a total melt down :-(

A couple hundred or so of these on the console.

Timer ISR/0: Time went backwards: delta=-9101039 cpu_delta=10898961
shadow=89150287265250 off=9333682407 processed8 0: 89159610048608
 1: 89159630000000
Timer ISR/0: Time went backwards: delta=-9144937 cpu_delta=10855063
shadow=89150287265250 off=9343638515 processed8 0: 89159620048608
 1: 89159640000000
Timer ISR/0: Time went backwards: delta=-8707693 cpu_delta=11292307
shadow=89150287265250 off=9354075736 processed8 0: 89159630048608
 1: 89159650000000


You guys putting any gremlins in this code :-)

Regards,
Ted

Re: Timer ISR/0: Time went backwards

[David F Barrera]

This is a know issue:

http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=195

Ted Kaczmarek wrote:

>On Fri, 2005-10-07 at 10:03 -0400, Ted Kaczmarek wrote:
>  
>
>>###############################################
>>changeset:   7234:bd37123974b2
>>Centos 4.1 dom0, Tyan 2462 SMP, 8k kernel stack
>>###############################################
>>
>>7 UP guests, have 1 very fat guest(1200 megs, running tomcat4,
>>postgresql, and opennms unstable) domain1, issuing 
>>xm save domain1;xm restore domain1
>>
>>saw these log messages.
>>
>>XEN) (file=grant_table.c, line=940) Grant unref rd(13) ld(0) frm(1a8cd)
>>flgs(1).
>>(XEN) (file=grant_table.c, line=940) Grant unref rd(13) ld(0) frm(1a614)
>>flgs(1).
>>
>>
>>DomU's exceeding 24 hours of uptime, other than issues related to load
>>on dom0 things are behaving rather well.
>>
>>Where can a user obtain docs on the grant tables by the way?
>>Is the source the only present place?
>>
>>
>>Regards
>>Ted
>>
>>
>>_______________________________________________
>>    
>>
>Within seconds of setting this a total melt down :-(
>
>A couple hundred or so of these on the console.
>
>Timer ISR/0: Time went backwards: delta=-9101039 cpu_delta=10898961
>shadow=89150287265250 off=9333682407 processed8 0: 89159610048608
> 1: 89159630000000
>Timer ISR/0: Time went backwards: delta=-9144937 cpu_delta=10855063
>shadow=89150287265250 off=9343638515 processed8 0: 89159620048608
> 1: 89159640000000
>Timer ISR/0: Time went backwards: delta=-8707693 cpu_delta=11292307
>shadow=89150287265250 off=9354075736 processed8 0: 89159630048608
> 1: 89159650000000
>
>
>You guys putting any gremlins in this code :-)
>
>Regards,
>Ted
>
>
>_______________________________________________
>Xen-devel mailing list
>Xen-devel@lists.xensource.com
>http://lists.xensource.com/xen-devel
>
>  
>

Timer ISR/0: Time went backwards

[Michal Ludvig]

Hi,

I'm running latest Xen from 3.0 HG repository (changeset 9762) on a 
laptop with VIA C7 CPU (i.e. x86 arch). Apart from the kernel the rest 
of the system is Kubuntu 6.06.

With Xen kernel I observe all different kinds of problems, all could be 
timer related. E.g. sometimes a pressed key on a keyboard is read 
multiple times, for example when I want to write "password" I may end up 
with "paaassword". Or from time to time in KDE either mouse or a keybord 
suddenly stops responding and I need to switch windows to make it 
running again (strange enough Alt-Tab always worked so far even when no 
other keys seemed to be accepted).

In dmesg I see suspicious messages like this:

Timer ISR/0: Time went backwards: delta=-58905320 delta_cpu=-54905320 
shadow=123279593111 off=13519708 processed=123352017015 
cpu_processed=123348017015
  0: 123348017015
Timer ISR/0: Time went backwards: delta=-49996903 delta_cpu=-45996903 
shadow=123279593111 off=22427259 processed=123352017015 
cpu_processed=123348017015
  0: 123348017015
[...]
psmouse.c: TouchPad at isa0060/serio4/input0 lost synchronization, 
throwing 2 bytes away.
psmouse.c: TouchPad at isa0060/serio4/input0 lost synchronization, 
throwing 3 bytes away.
psmouse.c: resync failed, issuing reconnect request
psmouse.c: TouchPad at isa0060/serio4/input0 lost synchronization, 
throwing 5 bytes away.

I tried recompiling the kernel with different timer and HZ settings, 
with and without REGPARM, but no luck so far.

Needless to say none of these problems exist when running original 
Ubuntu or vanilla non-Xen kernel (otherwise I wouldn't complain here ;-)

Any idea what can be wrong? I'm keen to run any tests or give you any 
other information you may need.

Thanks!

Michal