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RE: AW: RE: [Xen-devel] Time went backwards 885 ms

To: Carsten Schiers <carsten@xxxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: RE: AW: RE: [Xen-devel] Time went backwards 885 ms
From: Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>
Date: Sat, 28 Mar 2009 06:38:12 -0700 (PDT)
Cc:
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The fact that max cycles skew is so much smaller than max
stime (xen system time) skew leads me to believe that this
is a power management problem, and there's a good chance
it might be fixed already in xen-unstable (soon to be 3.4).

> -----Original Message-----
> From: Carsten Schiers [mailto:carsten@xxxxxxxxxx]
> Sent: Saturday, March 28, 2009 4:34 AM
> To: Dan Magenheimer; xen-devel
> Subject: AW: RE: [Xen-devel] Time went backwards 885 ms
> 
> 
> Ups sorry, missed the tail I guess you are only interested in the max 
> values...
> 
> BTW: during the measurement, there was a Time went Backwards in log:
> 
> Mar 28 10:47:15 data kernel: Timer ISR/0: Time went backwards: 
> delta=-67288961 delta_cpu=72711039 shadow=134369155097800 
> off=65631400 
> processed=134369288016520 cpu_processed=134369148016520
> Mar 28 10:47:15 data kernel:  0: 134369148016520
> Mar 28 10:47:15 data kernel:  1: 134369288016520
> 
> Will try to check on unstable soon...
> 
> BR,
> Carsten.
> 
> -----Ursprüngliche Nachricht-----
> Von: Carsten Schiers 
> Gesendet: Samstag, 28. März 2009 11:23
> An: dan.magenheimer; xen-devel
> Betreff: AW: RE: [Xen-devel] Time went backwards 885 ms
> 
> Here e.g. the last entries for Xen 3.3.1:
> 
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12670 current=256
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12671 
> current=36ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12671 current=449
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12672 
> current=60ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12672 current=257
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12673 
> current=19ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12673 current=382
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12674 
> current=7ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12674 current=48
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12675 
> current=54ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12675 current=382
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12676 
> current=16ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12676 current=445
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12677 
> current=49ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12677 current=508
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12678 
> current=90ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12678 current=62
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12679 
> current=14ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12679 current=292
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12680 
> current=21ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12680 current=193
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12681 
> current=88ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12681 current=143
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12682 
> current=56ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12682 current=382
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12683 
> current=1ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12683 current=33
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12684 
> current=18ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12684 current=4
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12685 
> current=56ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12685 current=370
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12686 
> current=7ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12686 current=48
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12687 
> current=7ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12687 current=48
> (XEN) Synced stime skew: max=297847ns avg=451ns samples=12688 
> current=44ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12688 current=366
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12689 
> current=53ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12689 current=369
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12690 
> current=75ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12690 current=382
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12691 
> current=31ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12691 current=78
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12692 
> current=124ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12692 current=289
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12693 
> current=80ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12693 current=330
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12694 
> current=22ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12694 current=256
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12695 
> current=79ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12695 current=373
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12696 
> current=97ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12696 current=382
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12697 
> current=119ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12697 current=382
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12698 
> current=140ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12698 current=382
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12699 
> current=164ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12699 current=334
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12700 
> current=160ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12700 current=370
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12701 
> current=122ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12701 current=382
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12702 
> current=74ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12702 current=175
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12703 
> current=65ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12703 current=102
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12704 
> current=89ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12704 current=62
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12705 
> current=85ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12705 current=116
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12706 
> current=5ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12706 current=188
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12707 
> current=10ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12707 current=31
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12708 
> current=57ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12708 current=65
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12709 
> current=54ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12709 current=295
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12710 
> current=119ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12710 current=77
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12711 
> current=108ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12711 current=47
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12712 
> current=78ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12712 current=52
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12713 
> current=57ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12713 current=49
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12714 
> current=26ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12714 current=42
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12715 
> current=56ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12715 current=62
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12716 
> current=9ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12716 current=53
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12717 
> current=10ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12717 current=52
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12718 
> current=1ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12718 current=33
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12719 
> current=109ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12719 current=175
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12720 
> current=0ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12720 current=36
> (XEN) Synced stime skew: max=297847ns avg=450ns samples=12721 
> current=17ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12721 current=256
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12722 
> current=85ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12722 current=422
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12723 
> current=92ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12723 current=492
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12724 
> current=50ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12724 current=387
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12725 
> current=94ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12725 current=490
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12726 
> current=43ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12726 current=382
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12727 
> current=60ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12727 current=57
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12728 
> current=48ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12728 current=287
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12729 
> current=57ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12729 current=62
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12730 
> current=5ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12730 current=251
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12731 
> current=90ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12731 current=169
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12732 
> current=38ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12732 current=62
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12733 
> current=189ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12733 current=345
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12734 
> current=6ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12734 current=256
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12735 
> current=52ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12735 current=62
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12736 
> current=46ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12736 current=294
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12737 
> current=90ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12737 current=465
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12738 
> current=50ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12738 current=382
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12739 
> current=51ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12739 current=382
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12740 
> current=53ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12740 current=330
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12741 
> current=62ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12741 current=382
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12742 
> current=47ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12742 current=62
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12743 
> current=4ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12743 current=292
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12744 
> current=56ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12744 current=330
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12745 
> current=7ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12745 current=48
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12746 
> current=87ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12746 current=382
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12747 
> current=93ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12747 current=328
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12748 
> current=28ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12748 current=98
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12749 
> current=29ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12749 current=102
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12750 
> current=112ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12750 current=382
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12751 
> current=138ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12751 current=372
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12752 
> current=108ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12752 current=339
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12753 
> current=85ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12753 current=335
> (XEN) Synced stime skew: max=297847ns avg=449ns samples=12754 
> current=61ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12754 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12755 
> current=18ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12755 current=256
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12756 
> current=3ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12756 current=170
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12757 
> current=122ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12757 current=22
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12758 
> current=150ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12758 current=285
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12759 
> current=269ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12759 current=408
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12760 
> current=246ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12760 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12761 
> current=179ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12761 current=52
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12762 
> current=165ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12762 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12763 
> current=149ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12763 current=490
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12764 
> current=5ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12764 current=256
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12765 
> current=60ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12765 current=193
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12766 
> current=33ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12766 current=545
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12767 
> current=108ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12767 current=256
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12768 
> current=25ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12768 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12769 
> current=51ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12769 current=285
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12770 
> current=88ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12770 current=103
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12771 
> current=56ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12771 current=373
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12772 
> current=94ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12772 current=134
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12773 
> current=53ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12773 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12774 
> current=5ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12774 current=217
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12775 
> current=53ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12775 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12776 
> current=21ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12776 current=297
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12777 
> current=11ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12777 current=256
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12778 
> current=20ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12778 current=47
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12779 
> current=15ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12779 current=48
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12780 
> current=9ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12780 current=251
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12781 
> current=48ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12781 current=79
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12782 
> current=70ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12782 current=382
> (XEN) Synced stime skew: max=297847ns avg=448ns samples=12783 
> current=65ns
> (XEN) Synced cycles skew: max=1142 avg=315 samples=12783 current=330
> 
> -----Ursprüngliche Nachricht-----
> Von: Carsten Schiers 
> Gesendet: Samstag, 28. März 2009 10:53
> An: dan.magenheimer; xen-devel
> Betreff: AW: RE: [Xen-devel] Time went backwards 885 ms
> 
> Oh, I didn't know that...
> 
> I started to do so. But not all lines will show up in xm 
> dmesg. Is there 
> 
> 
> 
> any trick to have a bigger buffer to capture it or are only the last 
> lines
> of interest?
> 
> BR,
> Carsten.
> 
> -----Ursprüngliche Nachricht-----
> Von: Dan Magenheimer [mailto:dan.magenheimer@xxxxxxxxxx] 
> Gesendet: Freitag, 27. März 2009 21:20
> An: Carsten Schiers; xen-devel
> Betreff: RE: [Xen-devel] Time went backwards 885 ms
> 
> Two possibilities... many power management features
> have gone into Xen and there are many bug fixes post-3.3
> to improve time sync in the presence of power management.
> 
> However if power management is NOT happening on your system,
> it's possible that your processors have bad TSC skew
> that Xen's TSC synchronization mechanism is unable to
> handle.  (This seems unlikely with a dual core... AMD
> might have information otherwise.)
> 
> A nice feature that went into Xen 3.3 is the ability to
> measure the skew between physical processors.  The
> "xm debug-key t" takes only one sample, but it can
> be repeated many times and will retain max and avg
> for all of the samples.
> 
> Can you do:
> 
> # for j in $(seq -w 10000); do xm debug-key t; done
>  
> in dom0, then send the output from "xm dmesg | tail"
> 
> If you can do this both with Xen 3.3 and 3.4 (when it
> is released, or xen-unstable now), that would be great!
> 
> -----Original Message-----
> From: Carsten Schiers [mailto:carsten@xxxxxxxxxx]
> Sent: Friday, March 27, 2009 3:19 AM
> To: xen-devel
> Subject: [Xen-devel] Time went backwards 885 ms
> 
> 
> Dear all,
> 
> I thought this might be worth again to report:
> 
> After rebooting a 3.3.1/2.6.18.8 environment on my AMD 4050e, 
> I received 
> 
> 
> a 885ms delta just
> after powernow-k8 loaded:
> 
> 
> Mar 26 21:28:37 data kernel: powernow-k8: Found 2 AMD Athlon(tm) Dual 
> Core Processor 4050e processors (version 2.20.00)
> Mar 26 21:28:37 data kernel: powernow-k8:    0 : fid 0xd 
> (2100 MHz), vid 
> 
> 
> 0xe
> Mar 26 21:28:37 data kernel: powernow-k8:    1 : fid 0xc 
> (2000 MHz), vid 
> 
> 
> 0xf
> Mar 26 21:28:37 data kernel: powernow-k8:    2 : fid 0xa 
> (1800 MHz), vid 
> 
> 
> 0x11
> Mar 26 21:28:37 data kernel: powernow-k8:    3 : fid 0x2 
> (1000 MHz), vid 
> 
> 
> 0x16
> Mar 26 21:28:37 data kernel: Timer ISR/1: Time went backwards: 
> delta=-885437842 delta_cpu=6562158 shadow=11822142480 off=436198 
> processed=12708016520 cpu_p
> rocessed=11816016520
> Mar 26 21:28:37 data kernel:  0: 12704016520
> Mar 26 21:28:37 data kernel:  1: 11816016520
> 
> 
> Find full xm dmesg, xm info, and syslog of boot attached.
> 
> Otherwise, the environment is more stable; Time went backwards appear 
> roughly every 2-3 days,
> mostly when there is a 1,0->2,1GHz jump when munin asks for 
> CPU. It is 
> reduced in addition by a
> 4 sec sampling time of the ondemand govenor.
> 
> Will test 3.4 as soon as released.
> 
> BR,
> Carsten.
> 
> 
> 
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