Re: cpu frequency
On Wed, Feb 4, 2015 at 3:06 AM, Nerijus Baliunas wrote: > On Tue, 3 Feb 2015 18:07:57 +0400 Andrey Korolyov wrote: > >> Have you tried to disable turbo mode (assuming you have new enough CPU >> model) and fix frequency via frequency governor` settings? If it >> helps, it can be an ugly hack with pre-up/post-up libvirt actions, >> though you`d probably want to keep frequency the same to maximize >> performance. > > I tried to alter frequency governor settings, but unsuccessfully. > They seem to change but then revert back in some short time. > CentOS 7, Intel(R) Xeon(R) CPU E5-2420 v2 @ 2.20GHz. > I remember that the floating frequency was resulted in incorrect guest CPU information, so may be it is an exact solution for your situation. Those frequency values could be altered by running service, unfortunately I have a not enough knowledge about Centos7 packages to name it. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
On Tue, 3 Feb 2015 18:07:57 +0400 Andrey Korolyov wrote: > Have you tried to disable turbo mode (assuming you have new enough CPU > model) and fix frequency via frequency governor` settings? If it > helps, it can be an ugly hack with pre-up/post-up libvirt actions, > though you`d probably want to keep frequency the same to maximize > performance. I tried to alter frequency governor settings, but unsuccessfully. They seem to change but then revert back in some short time. CentOS 7, Intel(R) Xeon(R) CPU E5-2420 v2 @ 2.20GHz. Regards, Nerijus -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
> It did not help. Today that commecrial application detects 2400, although > Control Panel -> System shows 2.20 GHz. > So my question again - is it possible to patch qemu-kvm that it shows some > constant frequency to the guest? But the answer is probably not, because > I don't know how the application computes the frequency... > Have you tried to disable turbo mode (assuming you have new enough CPU model) and fix frequency via frequency governor` settings? If it helps, it can be an ugly hack with pre-up/post-up libvirt actions, though you`d probably want to keep frequency the same to maximize performance. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
On 03/02/2015 14:25, Nerijus Baliunas wrote: > It did not help. Today that commecrial application detects 2400, although > Control Panel -> System shows 2.20 GHz. > So my question again - is it possible to patch qemu-kvm that it shows some > constant frequency to the guest? But the answer is probably not, because > I don't know how the application computes the frequency... Indeed. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
On Tue, 23 Dec 2014 15:40:22 +0100 Paolo Bonzini wrote: > > A commercial application running on Windows (kvm guest) detects CPU as: > > CPU_0: CPU0, Intel64 Family 6 Model 42 Stepping 1, 64, 64, 2200, > > 078BFBFD000206A1, 10753, CPU 0 > > After some time, without reboot, it detects as: > > CPU_0: CPU0, Intel64 Family 6 Model 42 Stepping 1, 64, 64, 2298, > > 078BFBFD000206A1, 10753, CPU 0 > > > > Windows Server 2012 Control Panel -> System shows CPU as 2.3 GHZ, but after > > reboot it might show 2.2 or 1.97 GHz. > > > > The problem is, that commercial application stops working after it detects > > CPU frequency change (2200 -> 2298 in above case). Is it possible to patch > > qemu-kvm that it shows some constant frquency to the guest? > > Do you know how the application computes the frequency? > > In the case of Windows it's probably some timing loop that is executed > at startup, and the result depends on frequency scaling in the host. > Try adding this to the XML in the meanwhile, and see if the control > panel shows the same value: > > Inside : > > > > > > Inside : > > > > Paolo It did not help. Today that commecrial application detects 2400, although Control Panel -> System shows 2.20 GHz. So my question again - is it possible to patch qemu-kvm that it shows some constant frequency to the guest? But the answer is probably not, because I don't know how the application computes the frequency... Regards, Nerijus -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
Nerijus Baliunas users.sourceforge.net> writes: > Paolo Bonzini redhat.com> writes: > > > In the case of Windows it's probably some timing loop that is executed > > at startup, and the result depends on frequency scaling in the host. > > Try adding this to the XML in the meanwhile, and see if the control > > panel shows the same value: > > > > Inside : > > > > > > > > > > > > Inside : > > > > > > So far Control Panel -> System shows CPU as 2.2 GHz, I rebooted once. So it > seems OK. Unfortunately after the host reboot the problem reappeared once. It helped to reboot the VM. Any ideas what else to try? Regards, Nerijus -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
Paolo Bonzini redhat.com> writes: > Do you know how the application computes the frequency? No. > In the case of Windows it's probably some timing loop that is executed > at startup, and the result depends on frequency scaling in the host. > Try adding this to the XML in the meanwhile, and see if the control > panel shows the same value: > > Inside : > > > > > > Inside : > > So far Control Panel -> System shows CPU as 2.2 GHz, I rebooted once. So it seems OK. Thanks, Nerijus -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
> A commercial application running on Windows (kvm guest) detects CPU as: > CPU_0: CPU0, Intel64 Family 6 Model 42 Stepping 1, 64, 64, 2200, > 078BFBFD000206A1, 10753, CPU 0 > After some time, without reboot, it detects as: > CPU_0: CPU0, Intel64 Family 6 Model 42 Stepping 1, 64, 64, 2298, > 078BFBFD000206A1, 10753, CPU 0 > > Windows Server 2012 Control Panel -> System shows CPU as 2.3 GHZ, but after > reboot it might show 2.2 or 1.97 GHz. > > The problem is, that commercial application stops working after it detects > CPU frequency change (2200 -> 2298 in above case). Is it possible to patch > qemu-kvm that it shows some constant frquency to the guest? Do you know how the application computes the frequency? In the case of Windows it's probably some timing loop that is executed at startup, and the result depends on frequency scaling in the host. Try adding this to the XML in the meanwhile, and see if the control panel shows the same value: Inside : Inside : Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
Paolo Bonzini redhat.com> writes: > How are you running qemu-kvm? (Command line, or XML if you're using > libvirt, or similar). XML - http://paste.fedoraproject.org/162378/14193357 command line - http://paste.fedoraproject.org/162379/93358231 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: cpu frequency
On 23/12/2014 12:19, Nerijus Baliunas wrote: > Hello, > > A commercial application running on Windows (kvm guest) detects CPU as: > CPU_0: CPU0, Intel64 Family 6 Model 42 Stepping 1, 64, 64, 2200, > 078BFBFD000206A1, 10753, CPU 0 > After some time, without reboot, it detects as: > CPU_0: CPU0, Intel64 Family 6 Model 42 Stepping 1, 64, 64, 2298, > 078BFBFD000206A1, 10753, CPU 0 > > Windows Server 2012 Control Panel -> System shows CPU as 2.3 GHZ, but after > reboot it might show 2.2 or 1.97 GHz. > > The problem is, that commercial application stops working after it detects > CPU frequency change (2200 -> 2298 in above case). Is it possible to patch > qemu-kvm that it shows some constant frquency to the guest? How are you running qemu-kvm? (Command line, or XML if you're using libvirt, or similar). Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
