My workstation is based on XEN, so you can see 'Xen' in the hostname in other threads. But this thread is all about KVM, I am testing KVM now. And I have already set 'options oprofile timer=1' in /etc/modprobe.conf of both host and guests.
So we DO NOT talk about neither 'hardware performance monitoring' nor XEN. Regards Kirby Zhou -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Robin Price II Sent: Friday, August 13, 2010 2:35 AM To: Red Hat Enterprise Linux 5 (Tikanga) discussion mailing-list Subject: Re: [rhelv5-list] oprofile works incorrectly under KVM guest? Kirby, Are you sure you are in full out KVM? I ask because your other thread titles KVM but your hostnames are set to Xen. I am going to assume you are doing Xen and share you some notes while getting oprofile to work in full virt Xen. Not sure if these applies to KVM but you can try. The full virtualization might be confusing oprofile kernel module. Virtualization doesn't allow access to the performance monitoring hardware. Oprofile identifies the process based on the cpuid (similar to method used for /proc/cpuinfo), based on the cpuid oprofile assumes that it can use the performance monitoring hardware. Try using "opcontrol --deinit; modprobe oprofile timer=1" to force oprofile to use the timer mechanism rather than the performance monitoring hardware. # opcontrol --deinit; modprobe oprofile timer=1 # opcontrol --start --vmlinux=/usr/lib/debug/lib/modules/`uname -r`/vmlinux --separate=library Need to stop oprofile, and unload the module ("opcontrol --deinit"), the modprobe makes sure that oprofile doesn't pay attention to the cpuid. 1) Assuming I do 'opcontrol --dump; oparchive --output-directory /output/path'. It should start saving data, correct? After doing the modprobe you will need do the "oprofile --setup ..." and "oprofile -start" to record data. Then you can do the experiment write the data and then oparchive it. Note that "opcontrol --shutdown" will automatically do the "opcontrol --dump" hope this helps. ~rp On Thu, Aug 12, 2010 at 4:38 AM, Kirby Zhou <[email protected]> wrote: > oprofile works incorrectly under KVM guest? > > If I do 'opcontrol --dump' outside the KVM guest, the output of opreport > inside the KVM guest will change. > > #Guest > [...@djt_10_192 ~]# opcontrol --start; opcontrol --reset; ./a.out 1 10000; > opcontrol --dump; opreport > Profiler running. > Signalling daemon... done > crc:a4580383 > CPU: CPU with timer interrupt, speed 0 MHz (estimated) > Profiling through timer interrupt > TIMER:0| > samples| %| > ------------------ > 13698 81.8084 no-vmlinux > 2417 14.4350 libcrypto.so.0.9.8e > 473 2.8249 libz.so.1.2.3 > 58 0.3464 a.out > 42 0.2508 libc-2.5.so > 34 0.2031 ld-2.5.so > 14 0.0836 bash > 4 0.0239 gawk > 2 0.0119 oprofiled > 1 0.0060 GBK.so > 1 0.0060 libstdc++.so.6.0.8 > > #Host > [...@djt_10_48 ~]# opcontrol --dump > #Guest > [...@djt_10_192 ~]# opreport > CPU: CPU with timer interrupt, speed 0 MHz (estimated) > Profiling through timer interrupt > TIMER:0| > samples| %| > ------------------ > 336162 98.9203 no-vmlinux > 2422 0.7127 libcrypto.so.0.9.8e > 473 0.1392 libz.so.1.2.3 > 335 0.0986 opreport > 156 0.0459 libc-2.5.so > 94 0.0277 ld-2.5.so > 58 0.0171 a.out > 34 0.0100 bash > 34 0.0100 oprofiled > 33 0.0097 libstdc++.so.6.0.8 > 15 0.0044 gawk > 6 0.0018 less > 4 0.0012 GBK.so > 2 5.9e-04 grep > 1 2.9e-04 sed > 1 2.9e-04 libm-2.5.so > 1 2.9e-04 sshd > [...@djt_10_192 ~]# > > Regards, > Kirby Zhou > from SOHU-RD +86-10-6272-8261 > > > > _______________________________________________ > rhelv5-list mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/rhelv5-list > _______________________________________________ rhelv5-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv5-list _______________________________________________ rhelv5-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv5-list
