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. -- 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
