On Tue, Apr 03, 2012 at 07:20:04PM +0530, shashank rachamalla wrote: > On Mon, Mar 19, 2012 at 12:37 PM, Gleb Natapov <gleb@xxxxxxxxxx> wrote: > > On Mon, Mar 19, 2012 at 12:20:30PM +0530, shashank rachamalla wrote: > >> On Sun, Mar 18, 2012 at 10:21 PM, Gleb Natapov <gleb@xxxxxxxxxx> wrote: > >> > On Sun, Mar 18, 2012 at 09:47:55PM +0530, shashank rachamalla wrote: > >> >> >> I guess things are working fine with perf. But why not with oprofile ? > >> >> >> > >> >> > Looks like it. I never tried oprofile. Will try to reproduce your > >> >> > problem and see what oprofile is doing. > >> >> > >> >> I am using ubuntu 10.04 with 2.6.32-21-generic kernel as guest and > >> >> oprofile 0.9.6. > >> >> Also, I have tried to capture kvm-events ( perf patch ) in host while > >> >> running oprofile and perf in guest. > >> >> Please see the attachment. I have run the tests in three cases for the > >> >> around 5 secs. > >> >> > >> >> There are more number of MSR reads and writes in case of perf which I > >> >> think is normal. However, there are very few MSR reads and writes with > >> >> oprofile. Also, the number of NMI exceptions are too high in case of > >> >> oprofile. > >> >> > >> > Which host kernel are you using? Try latest kvm.git and check if you see > >> > something unusual in dmesg. > >> > >> Currenly running 3.3.0-rc5. will try with the latest source from kvm > >> git and let you know. > >> > >> > > Thanks, there were some fixes that didn't make it into 3.3. rdpmc > > instruction emulation fix is one of them. If oprofile uses it this can > > explain the problem. > > > I have tried with latest kvm source from git and also with 3.0 guest > kernel but oprofile fails to collect any samples on guest. I am using > a core2duo processor which is considered by oprofile as pentium pro > model. > core2duo on the host or the guest? What is your qemu command line? -- Gleb. -- 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
