On Mon, 2010-10-18 at 17:35 +0200, Jan Kiszka wrote: > Am 18.10.2010 17:24, Steven Rostedt wrote: > > On Mon, 2010-10-18 at 17:08 +0200, Jan Kiszka wrote: > > > >>> Just to summarize: > >>> - on real HW with rtai-patch the issue is caused by rtai > >>> - the vanilla kernel used with vmware has some other issues > >> > >> I missed the vanilla part: Can you reproduce under QEMU/KVM? Debugging > >> the guest would be easier then, and it's easier to trace what that > >> hypervisor does. Maybe there is a subtle race in the test code that is > >> exposed by the timing that virtualization implies. > > > > Note, there was a bug fixed due to pv ops and kvm clock being traced: > > > > http://lkml.org/lkml/2010/9/22/455 > > > > The two fixes are next in that thread. > > Alternatively, this should avoid running into the code paths: > > qemu-system-x86_64 [...] -cpu kvm64,-kvmclock > (ie. claim that we don't support kvmclock) Wouldn't that cause a slowdown in performance? Also, does this keep from using pvclock too? -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-trace-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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