Hi Ahmad, I''m certainly not a Xenoprof expert, but I''ve learned a bit about it by trial and error, with help from the xen-devel list. I''ve taken the liberty of Cc:ing xen-devel so that others more knowledgeable than me can help you. I haven''t tried passive domains yet, and I''ll say up front that I don''t know why Xenoprof isn''t working for you with passive domains. On 02/11/10 13:37, Ahmad Hassan wrote:> Hi Andrew, > > I need help in using xenoprof. I installed the xenoprof on Dom0 and > DomU as follows: > > * Download Oprofile: > http://prdownloads.sourceforge.net/oprofile/oprofile-0.9.5.tar.gz > * Download XenoProf > patch: http://xenoprof.sourceforge.net/oprofile-0.9.5-xen.patch > * tar –zxvf oprofile-0.9.5.tar.gz > * cd oprofile-0.9.5 > * patch –p1 < ../oprofile-0.9.5-xen-rc2.patch ./configure > –with-kernel-support > * make > * make install >That looks right to me. You also need Xenoprof support in your dom0 kernel. If you''re using one of the kernels from the Xen source tree and you can `modprobe oprofile` successfully, you should be ok.> I am interested in measuring profiling overhead in XEN. So which kind > of event should I capture.You want to measure the overhead of the profiler itself? I guess you get that "for free" -- time spent in oprofile kernel code should show up in opreport in dom0, I think. Which performance counter you use depends on what you''re trying to measure. If you just want to find out where CPU time is spent, CPU_CLK_UNHALTED should do that for you. That''s what I''ve been doing.> Is it possible to capture all the events?You can specify multiple events, though I haven''t tried it. The opreport web page talks about output for multiple events here: http://oprofile.sourceforge.net/doc/opreport.html#opreport-comparison I''d guess you''d just specify --event multiple times when you --start-daemon.> I followed the following passive profiling approach but I did not > get any data. > > Dom0: opcontrol --reset > Dom1: opcontrol --reset > Dom0: opcontrol --start-daemon --event> CPU_IO_REQUESTS_TO_MEMORY_IO:1000000 --xen=/boot/xen-syms-3.4.1 > --vmlinux=/boot/vmlinux --passive-domains=1 > --passive-images=/boot/vmlinux > *At the above command, I get the warning as : > /dev/oprofile/passive-domains Permission Denied* but daemon starts > eventuallyThis is a silly question, but you are running this as root, correct? If you are running as root and getting this error, I think something is wrong either in Xen or your dom0 kernel. `xm dmesg` may have error messages that give clues -- check it before and after starting the daemon.> Dom0: opcontrol --start > AFTER 30 MINUTE > Dom0: opcontrol –stop > Dom0: opcontrol --dump > Dom0: opcontrol –shutdown > > But when I try to "opreport -l" ti says that: "opreport error: No > sample file found: try running opcontrol --dump or specfiy a session > containing sample file" > > > Can you please help me in that? > > Thanks. > > Best Regards, Hassan > http://cern.ch/ahmadh/portfolio > > Erasmus Student > The University of Reading, UK > Aristotle University of Thessaloniki, Greece > The University Of Carlos III, Madrid Spain > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Hi Andrew, Thanks for the message. That looks right to me. You also need Xenoprof support in your dom0 kernel.> If you''re using one of the kernels from the Xen source tree and you can > `modprobe oprofile` successfully, you should be ok. >Yes I loaded the oprofile as "modprobe oprofile". It loads successfully.> > > Dom0: opcontrol --start-daemon --event= CPU_IO_REQUESTS_TO_MEMORY_IO:1000000 > --xen=/boot/xen-syms-3.4.1 --vmlinux=/boot/vmlinux --passive-domains=1 > --passive-images=/boot/vmlinux > *At the above command, I get the warning as : > /dev/oprofile/passive-domains Permission Denied* but daemon starts > eventually > >If i start the Dom0 daemon for passive domains using the above command the the following exact output I get *At the above command, I get the warning as : /dev/oprofile/passive-domains Permission Denied* *Using* *2*.*6*+ *OProfile* *kernel* interface. *Using* *log* *file* /*var*/*lib*/*oprofile*/*oprofiled*.*log* *Daemon* *started*. *Profiler* *running* Yes I am running it as a root. If I look at the * /dev/oprofile the I don''t find any file name passive-domains. Opreport -l shows the following error: * "opreport error: No sample file found: try running opcontrol --dump or specfiy a session containing sample file" When I try active-domains option then inside DomU, I get the following error while starting the daemon: *"You cannot specify any performance counter events because OProfile is in timer mode.*" Why the above error appears for active domains? Do I need to pass "lapic" parameter in the grub file of dom0? Thanks for the help Best Regards, Hassan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Acive domain profiling has not been well tested with pvops kernel. Dulloor who ported xenoprof parches to the pvops kernel said in a previous post that he would look into that but not sure if he did. For now your alternatives are: - Use passive domain prifiling instead - Use 2.6.18-xen with Xen 4.0 or latest unstable which are known to work with active domain profiling Renato ________________________________ From: xen-devel-bounces@lists.xensource.com [mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Andrew Evans Sent: Thursday, February 11, 2010 3:39 PM To: Ahmad Hassan Cc: xen-devel@lists.xensource.com Subject: [Xen-devel] Re: XENOPROF Problem Hi Ahmad, I''m certainly not a Xenoprof expert, but I''ve learned a bit about it by trial and error, with help from the xen-devel list. I''ve taken the liberty of Cc:ing xen-devel so that others more knowledgeable than me can help you. I haven''t tried passive domains yet, and I''ll say up front that I don''t know why Xenoprof isn''t working for you with passive domains. On 02/11/10 13:37, Ahmad Hassan wrote: Hi Andrew, I need help in using xenoprof. I installed the xenoprof on Dom0 and DomU as follows: * Download Oprofile: http://prdownloads.sourceforge.net/oprofile/oprofile-0.9.5.tar.gz * Download XenoProf patch: http://xenoprof.sourceforge.net/oprofile-0.9.5-xen.patch * tar -zxvf oprofile-0.9.5.tar.gz * cd oprofile-0.9.5 * patch -p1 < ../oprofile-0.9.5-xen-rc2.patch ./configure -with-kernel-support * make * make install That looks right to me. You also need Xenoprof support in your dom0 kernel. If you''re using one of the kernels from the Xen source tree and you can `modprobe oprofile` successfully, you should be ok. I am interested in measuring profiling overhead in XEN. So which kind of event should I capture. You want to measure the overhead of the profiler itself? I guess you get that "for free" -- time spent in oprofile kernel code should show up in opreport in dom0, I think. Which performance counter you use depends on what you''re trying to measure. If you just want to find out where CPU time is spent, CPU_CLK_UNHALTED should do that for you. That''s what I''ve been doing. Is it possible to capture all the events? You can specify multiple events, though I haven''t tried it. The opreport web page talks about output for multiple events here: http://oprofile.sourceforge.net/doc/opreport.html#opreport-comparison I''d guess you''d just specify --event multiple times when you --start-daemon. I followed the following passive profiling approach but I did not get any data. Dom0: opcontrol --reset Dom1: opcontrol --reset Dom0: opcontrol --start-daemon --event= CPU_IO_REQUESTS_TO_MEMORY_IO:1000000 --xen=/boot/xen-syms-3.4.1 --vmlinux=/boot/vmlinux --passive-domains=1 --passive-images=/boot/vmlinux At the above command, I get the warning as : /dev/oprofile/passive-domains Permission Denied but daemon starts eventually This is a silly question, but you are running this as root, correct? If you are running as root and getting this error, I think something is wrong either in Xen or your dom0 kernel. `xm dmesg` may have error messages that give clues -- check it before and after starting the daemon. Dom0: opcontrol --start AFTER 30 MINUTE Dom0: opcontrol -stop Dom0: opcontrol --dump Dom0: opcontrol -shutdown But when I try to "opreport -l" ti says that: "opreport error: No sample file found: try running opcontrol --dump or specfiy a session containing sample file" Can you please help me in that? Thanks. Best Regards, Hassan http://cern.ch/ahmadh/portfolio Erasmus Student The University of Reading, UK Aristotle University of Thessaloniki, Greece The University Of Carlos III, Madrid Spain _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel