Messages in this thread | | | From | Namhyung Kim <> | Date | Wed, 22 Sep 2021 12:34:20 -0700 | Subject | Re: [PATCH v2] perf/core: Add a new read format to get a number of lost samples |
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Hi Peter,
On Fri, Sep 10, 2021 at 3:40 PM Namhyung Kim <namhyung@kernel.org> wrote: > > On Fri, Sep 10, 2021 at 2:42 PM Jiri Olsa <jolsa@redhat.com> wrote: > > > > On Wed, Sep 08, 2021 at 10:24:20AM -0700, Namhyung Kim wrote: > > > Sometimes we want to know an accurate number of samples even if it's > > > lost. Currenlty PERF_RECORD_LOST is generated for a ring-buffer which > > > might be shared with other events. So it's hard to know per-event > > > lost count. > > > > > > Add event->lost_samples field and PERF_FORMAT_LOST to retrieve it from > > > userspace. > > > > hi, > > looks good.. will there be some tools/perf change using this? > > Sure, I'll work on the userspace part after this is merged. > I'm thinking about adding LOST_SAMPLES records at the end > of the data section as if they came from the kernel.
Can I get your feedback?
Thanks, Namhyung
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