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    SubjectRe: [PATCH 2/3] perf/x86/intel/pt: Add an option to not force PSB+ on every schedule-in
    Date
    Alexander Shishkin <alexander.shishkin@linux.intel.com> writes:

    > It kinda does make a difference: inside PSB+ you get a TSC packet, which
    > carries the tsc timestamp as a payload, so, with the current behavior,
    > since you'll get one of those at every event schedule-in, you'll have
    > many more time synchronization points with the perf stream, but when the
    > default changes, suddenly your timestamps way further apart and the
    > decoder needs to put in additional guesswork to correlate those MMAP
    > events in the perf stream with the PT trace.

    I spoke hastily, TSC packets will be generated on every schedule-in (as
    well as other packets that normally come in PSB+) regardless of the
    actual PSB, so scratch the above. Let me replace the above with a
    smaller patch.

    Regards,
    --
    Alex


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