Hello All, I''m getting the following error from one of my guest domains (domain 1).. Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -124000 1367865 0000000 9876000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -109000 1367865 0000000 9891000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -94000 13678650 000000 9906000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -82000 13678650 000000 9918000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -66000 13678650 000000 9934000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -52000 13678650 000000 9948000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -37000 13678650 000000 9963000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -24000 13678650 000000 9976000 13678660000000 Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -6000 136786500 00000 9994000 13678660000000 Anyone else seen this or know what to do about it? The main system isn''t experiencing any related errors of this sort.... Thanks, Jeremy ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
How often do you get these messages? It is only showing you to be out by about 130us, but I don''t really see how even that can happen. Also, the rate at which the below stream is coming out is about one error per 15us, which is very rapid indeed. Is this running on CPU0 or CPU1 (on an SMP system)? You might want to try changing the start of do_timer_interrupt() in arch/xen/i386/kernel/time.c to what I have attached just below. Another thing is to build Xen with performance counters (perfc=y make) and then use the xenperf utility to see how many times Xen''s scheduler is being entered (this might account for the high rate of timer interrupts you are seeing). Also looking at cat /proc/interrupts in DOM1 may be interesting... -- Keir static inline void do_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { time_t wtm_sec, sec; s64 delta, nsec; long sec_diff, wtm_nsec; /* XXX New declarations below. */ static s64 pdelta, pshadow, pprocessed, poffset; do { __get_time_values_from_xen(); delta = (s64)(shadow_system_time + ((s64)cur_timer->get_offset() * (s64)NSEC_PER_USEC) - processed_system_time); } while (!TIME_VALUES_UP_TO_DATE); if (unlikely(delta < 0)) { printk("Timer ISR: Time went backwards: %lld %lld %lld %lld\n", delta, shadow_system_time, ((s64)cur_timer->get_offset() * (s64)NSEC_PER_USEC), processed_system_time); /* XXX New printk below. &/ printk(" ** %lld %lld %lld %lld\n", pdelta, pshadow, pprocessed, poffset); return; } /* XXX New assignments below. */ pdelta = delta; pshadow = shadow_system_time; pprocessed = processed_system_time; poffset = (s64)cur_timer->get_offset();> Hello All, > > I''m getting the following error from one of my guest domains (domain 1).. > > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -124000 > 1367865 > 0000000 9876000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -109000 > 1367865 > 0000000 9891000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -94000 > 13678650 > 000000 9906000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -82000 > 13678650 > 000000 9918000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -66000 > 13678650 > 000000 9934000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -52000 > 13678650 > 000000 9948000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -37000 > 13678650 > 000000 9963000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -24000 > 13678650 > 000000 9976000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -6000 > 136786500 > 00000 9994000 13678660000000 > > Anyone else seen this or know what to do about it? > > The main system isn''t experiencing any related errors of this sort.... > > Thanks, > Jeremy > > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://productguide.itmanagersjournal.com/ > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xen-devel------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
They''re pretty intermittent, so its hard to give an exact guess. The host system is a dual xeon 2.4 with HTT.. here''s some info: Host: vlink:~# xm info system : Linux host : vlink release : 2.6.9-xen0 version : #4 Fri Dec 3 22:00:29 EST 2004 machine : i686 cores : 2 hyperthreads_per_core : 2 cpu_mhz : 2399 memory : 1023 free_memory : 622 vlink:~# xm list Name Id Mem(MB) CPU State Time(s) Console Domain-0 0 123 0 r---- 65.2 vlink 3 255 1 -b--- 27.1 9603 vlink:~# cat /proc/interrupts CPU0 14: 20730 Phys-irq ide0 18: 435145 Phys-irq eth1 19: 467659 Phys-irq eth0 128: 1 Dynamic-irq misdirect 129: 41 Dynamic-irq ctrl-if 130: 136374838 Dynamic-irq timer 131: 40 Dynamic-irq console 132: 0 Dynamic-irq net-be-dbg 133: 11859 Dynamic-irq blkif-backend 134: 1439 Dynamic-irq vif3.0 NMI: 0 ERR: 0 Guest Info: iad1-uml:/var/log# cat /proc/interrupts CPU0 128: 1 Dynamic-irq misdirect 129: 19804 Dynamic-irq ctrl-if 130: 118967169 Dynamic-irq timer 131: 10672 Dynamic-irq blkif 132: 1705 Dynamic-irq eth0 NMI: 0 ERR: 0 Thanks, Jeremy Keir Fraser said:> > How often do you get these messages? It is only showing you to be out > by about 130us, but I don''t really see how even that can happen. Also, > the rate at which the below stream is coming out is about one error > per 15us, which is very rapid indeed. Is this running on CPU0 or CPU1 > (on an SMP system)? > > You might want to try changing the start of do_timer_interrupt() in > arch/xen/i386/kernel/time.c to what I have attached just below. > > Another thing is to build Xen with performance counters (perfc=y make) > and then use the xenperf utility to see how many times Xen''s scheduler > is being entered (this might account for the high rate of timer > interrupts you are seeing). Also looking at cat /proc/interrupts in > DOM1 may be interesting... > > -- Keir > > static inline void do_timer_interrupt(int irq, void *dev_id, > struct pt_regs *regs) > { > time_t wtm_sec, sec; > s64 delta, nsec; > long sec_diff, wtm_nsec; > /* XXX New declarations below. */ > static s64 pdelta, pshadow, pprocessed, poffset; > > do { > __get_time_values_from_xen(); > > delta = (s64)(shadow_system_time + > ((s64)cur_timer->get_offset() * > (s64)NSEC_PER_USEC) - > processed_system_time); > } > while (!TIME_VALUES_UP_TO_DATE); > > if (unlikely(delta < 0)) { > printk("Timer ISR: Time went backwards: %lld %lld %lld > %lld\n", > delta, shadow_system_time, > ((s64)cur_timer->get_offset() * > (s64)NSEC_PER_USEC), > processed_system_time); > /* XXX New printk below. &/ > printk(" ** %lld %lld %lld %lld\n", > pdelta, pshadow, pprocessed, poffset); > return; > } > > /* XXX New assignments below. */ > pdelta = delta; > pshadow = shadow_system_time; > pprocessed = processed_system_time; > poffset = (s64)cur_timer->get_offset(); > > >> Hello All, >> >> I''m getting the following error from one of my guest domains (domain >> 1).. >> >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -124000 >> 1367865 >> 0000000 9876000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -109000 >> 1367865 >> 0000000 9891000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -94000 >> 13678650 >> 000000 9906000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -82000 >> 13678650 >> 000000 9918000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -66000 >> 13678650 >> 000000 9934000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -52000 >> 13678650 >> 000000 9948000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -37000 >> 13678650 >> 000000 9963000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -24000 >> 13678650 >> 000000 9976000 13678660000000 >> Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -6000 >> 136786500 >> 00000 9994000 13678660000000 >> >> Anyone else seen this or know what to do about it? >> >> The main system isn''t experiencing any related errors of this sort.... >> >> Thanks, >> Jeremy >> >> >> >> ------------------------------------------------------- >> SF email is sponsored by - The IT Product Guide >> Read honest & candid reviews on hundreds of IT Products from real users. >> Discover which products truly live up to the hype. Start reading now. >> http://productguide.itmanagersjournal.com/ >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/xen-devel > >------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
I had this error once when running benchmarks and the guest''s RAM ran out, adding swap helped in that situation. On Sun, 12 Dec 2004 16:56:29 -0500 (EST) "Jeremy Miracle" <jeremy@vlink.us> wrote:> Hello All, > > I''m getting the following error from one of my guest domains (domain 1).. > > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -124000 > 1367865 > 0000000 9876000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -109000 > 1367865 > 0000000 9891000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -94000 > 13678650 > 000000 9906000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -82000 > 13678650 > 000000 9918000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -66000 > 13678650 > 000000 9934000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -52000 > 13678650 > 000000 9948000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -37000 > 13678650 > 000000 9963000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -24000 > 13678650 > 000000 9976000 13678660000000 > Dec 12 16:41:00 iad1-uml kernel: Timer ISR: Time went backwards: -6000 > 136786500 > 00000 9994000 13678660000000 > > Anyone else seen this or know what to do about it? > > The main system isn''t experiencing any related errors of this sort.... > > Thanks, > Jeremy > > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://productguide.itmanagersjournal.com/ > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xen-devel >------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel