Thanks for the answer. I am more of an application user. Is there a quick way to check this flag and enable it if its disabled? Abhishek On Mon, Oct 8, 2012 at 2:39 PM, Marcelo Tosatti <mtosatti@xxxxxxxxxx> wrote: > On Mon, Oct 08, 2012 at 02:55:25AM -0500, Abhishek Gupta wrote: >> Hi, >> >> I am trying to get the steal time with 2 VMs (each with 1 Vcpu) pinned >> to same core. >> >> While finding documentation on this, I came across your patches and >> posts related to the implementation of this feature, so I thought it >> would be best to ask you. >> >> I run the same application on these 2 VMs simultaneously and see the >> performance difference. I am trying to read the steal time from inside >> the guest using top, vmstat etc. >> >> Both, top and vmstat -s report the steal time (st) as 0. I also >> checked that procps is in latest version. I am using virtio-net. I >> suspect that the steal time is not being updated well. Is there >> something which I need to configure for this to work? My Linux version >> for guest image is: >> >> Linux server-147 2.6.35-24-virtual #42-Ubuntu SMP Thu Dec 2 05:15:26 >> UTC 2010 x86_64 GNU/Linux >> >> And /proc/cpuinfo shows i: >> >> processor : 0 >> vendor_id : GenuineIntel >> cpu family : 6 >> model : 2 >> model name : QEMU Virtual CPU version 0.14.0 >> stepping : 3 >> cpu MHz : 2992.498 >> cache size : 4096 KB >> fpu : yes >> fpu_exception : yes >> cpuid level : 4 >> wp : yes >> flags : fpu de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov >> pse36 clflush mmx fxsr sse sse2 syscall nx lm up rep_good pni cx16 >> hypervisor lahf_lm > bogomips : 5984.99 >> clflush size : 64 >> cache_alignment : 64 >> address sizes : 40 bits physical, 48 bits virtual >> power management: >> >> >> Another question I had was that is there a way to programmatically get >> the value of steal cycles (e.g. from a C program) ? >> Thanks, >> >> Abhishek > > Make sure CONFIG_SCHEDSTATS is enabled in your host kernel. > >> On Monday, June 13, 2011 6:40:02 PM UTC-5, Glauber Costa wrote: >> > Hi, >> > >> > This series is a repost of the last series I posted about this. >> > It tries to address most concerns that were raised at the time, >> > plus makes uses of the static_branch interface to disable the >> > steal code when not in use. >> > >> > >> > Glauber Costa (7): >> > KVM-HDR Add constant to represent KVM MSRs enabled bit >> > KVM-HDR: KVM Steal time implementation >> > KVM-HV: KVM Steal time implementation >> > KVM-GST: Add a pv_ops stub for steal time >> > KVM-GST: KVM Steal time accounting >> > KVM-GST: adjust scheduler cpu power >> > KVM-GST: KVM Steal time registration >> > >> > Documentation/kernel-parameters.txt | 4 ++ >> > Documentation/virtual/kvm/msr.txt | 33 +++++++++++++ >> > arch/x86/Kconfig | 12 +++++ >> > arch/x86/include/asm/kvm_host.h | 8 +++ >> > arch/x86/include/asm/kvm_para.h | 15 ++++++ >> > arch/x86/include/asm/paravirt.h | 9 ++++ >> > arch/x86/include/asm/paravirt_types.h | 1 + >> > arch/x86/kernel/kvm.c | 72 +++++++++++++++++++++++++++++ >> > arch/x86/kernel/kvmclock.c | 2 + >> > arch/x86/kernel/paravirt.c | 9 ++++ >> > arch/x86/kvm/x86.c | 60 +++++++++++++++++++++++- >> > kernel/sched.c | 81 +++++++++++++++++++++++++++++---- >> > kernel/sched_features.h | 4 +- >> > 13 files changed, 296 insertions(+), 14 deletions(-) >> > >> > -- >> > 1.7.3.4 >> > >> > -- >> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> > the body of a message to majordomo@xxxxxxxxxxxxxxx >> > More majordomo info at http://vger.kernel.org/majordomo-info.html >> > Please read the FAQ at http://www.tux.org/lkml/ >> >> >> >> On Monday, June 13, 2011 6:40:02 PM UTC-5, Glauber Costa wrote: >> > Hi, >> > >> > This series is a repost of the last series I posted about this. >> > It tries to address most concerns that were raised at the time, >> > plus makes uses of the static_branch interface to disable the >> > steal code when not in use. >> > >> > >> > Glauber Costa (7): >> > KVM-HDR Add constant to represent KVM MSRs enabled bit >> > KVM-HDR: KVM Steal time implementation >> > KVM-HV: KVM Steal time implementation >> > KVM-GST: Add a pv_ops stub for steal time >> > KVM-GST: KVM Steal time accounting >> > KVM-GST: adjust scheduler cpu power >> > KVM-GST: KVM Steal time registration >> > >> > Documentation/kernel-parameters.txt | 4 ++ >> > Documentation/virtual/kvm/msr.txt | 33 +++++++++++++ >> > arch/x86/Kconfig | 12 +++++ >> > arch/x86/include/asm/kvm_host.h | 8 +++ >> > arch/x86/include/asm/kvm_para.h | 15 ++++++ >> > arch/x86/include/asm/paravirt.h | 9 ++++ >> > arch/x86/include/asm/paravirt_types.h | 1 + >> > arch/x86/kernel/kvm.c | 72 +++++++++++++++++++++++++++++ >> > arch/x86/kernel/kvmclock.c | 2 + >> > arch/x86/kernel/paravirt.c | 9 ++++ >> > arch/x86/kvm/x86.c | 60 +++++++++++++++++++++++- >> > kernel/sched.c | 81 +++++++++++++++++++++++++++++---- >> > kernel/sched_features.h | 4 +- >> > 13 files changed, 296 insertions(+), 14 deletions(-) >> > >> > -- >> > 1.7.3.4 >> > >> > -- >> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> > the body of a message to majordomo@xxxxxxxxxxxxxxx >> > More majordomo info at http://vger.kernel.org/majordomo-info.html >> > Please read the FAQ at http://www.tux.org/lkml/ >> -- >> To unsubscribe from this list: send the line "unsubscribe kvm" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
