* Zhang, Yanmin <yanmin_zhang@xxxxxxxxxxxxxxx> wrote: > On Tue, 2010-03-16 at 15:48 +0800, Zhang, Yanmin wrote: > > On Tue, 2010-03-16 at 07:41 +0200, Avi Kivity wrote: > > > On 03/16/2010 07:27 AM, Zhang, Yanmin wrote: > > > > From: Zhang, Yanmin<yanmin_zhang@xxxxxxxxxxxxxxx> > > > > > > > > Based on the discussion in KVM community, I worked out the patch to support > > > > perf to collect guest os statistics from host side. This patch is implemented > > > > with Ingo, Peter and some other guys' kind help. Yang Sheng pointed out a > > > > critical bug and provided good suggestions with other guys. I really appreciate > > > > their kind help. > > > > > > > > The patch adds new subcommand kvm to perf. > > > > > > > > perf kvm top > > > > perf kvm record > > > > perf kvm report > > > > perf kvm diff > > > > > > > > The new perf could profile guest os kernel except guest os user space, but it > > > > could summarize guest os user space utilization per guest os. > > > > > > > > Below are some examples. > > > > 1) perf kvm top > > > > [root@lkp-ne01 norm]# perf kvm --host --guest --guestkallsyms=/home/ymzhang/guest/kallsyms > > > > --guestmodules=/home/ymzhang/guest/modules top > > > > > > > > > > > > > Thanks for your kind comments. > > > > > Excellent, support for guest kernel != host kernel is critical (I can't > > > remember the last time I ran same kernels). > > > > > > How would we support multiple guests with different kernels? > > With the patch, 'perf kvm report --sort pid" could show > > summary statistics for all guest os instances. Then, use > > parameter --pid of 'perf kvm record' to collect single problematic instance data. > Sorry. I found currently --pid isn't process but a thread (main thread). > > Ingo, > > Is it possible to support a new parameter or extend --inherit, so 'perf > record' and 'perf top' could collect data on all threads of a process when > the process is running? > > If not, I need add a new ugly parameter which is similar to --pid to filter > out process data in userspace. Yeah. For maximum utility i'd suggest to extend --pid to include this, and introduce --tid for the previous, limited-to-a-single-task functionality. Most users would expect --pid to work like a 'late attach' - i.e. to work like strace -f or like a gdb attach. Ingo -- 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
