Re: [Qemu-devel] Question on kvm_clock working ...

2011-09-26 Thread Ronen Hod
On 09/09/2011 06:28 PM, al pat wrote: We are doing an experiment with kvm-clock to validate its effectiveness, particularly when running NTP on the host to make sure the host’s clock stays properly sync. Our observations leads us to a few unanswered questions, including the possibility of a

Re: [Qemu-devel] Question on kvm_clock working ...

2011-09-15 Thread al pat
Hi Phil, Thanks for an excellent explanation. Follow up question - ...additional clock source named kvmclock, which uses the host clock and the TSC: The host exports its current system time (plus some configurable offset) and a snapshot value of TSC register when doing so. Than the guest can

Re: [Qemu-devel] Question on kvm_clock working ...

2011-09-13 Thread Philipp Hahn
Hello Al, I just debugged a kvmclock bug, so I claim to have some knowledge in this area now, but please take my answer with a grain of doubt. On Monday 12 September 2011 15:21:25 al pat wrote: Still seeking your guidance on this. Appreciate any pointers you may have. You have to distiguish

Re: [Qemu-devel] Question on kvm_clock working ...

2011-09-13 Thread al pat
Thanks Phillip. My current source is kvm-clock. WHen I start my guest, it is in sync with the host clock. Then, I chance the time on my host - using date --set I don't see the guest update its time. I was expecting that the guest will detect host time change and change it? So, when the

Re: [Qemu-devel] Question on kvm_clock working ...

2011-09-13 Thread Jan Kiszka
On 2011-09-13 13:38, al pat wrote: Thanks Phillip. My current source is kvm-clock. WHen I start my guest, it is in sync with the host clock. Then, I chance the time on my host - using date --set I don't see the guest update its time. I was expecting that the guest will detect host

Re: [Qemu-devel] Question on kvm_clock working ...

2011-09-12 Thread al pat
Hi Folks, Still seeking your guidance on this. Appreciate any pointers you may have. Thanks much. -a On Fri, Sep 9, 2011 at 11:28 AM, al pat alps@gmail.com wrote: We are doing an experiment with kvm-clock to validate its effectiveness, particularly when running NTP on the host to make