title: perf - filtering a specifc period
body: <p>we have the <code>perf</code> tool for Linux and <code>perf record</code> family command. By family I mean
  <code>perf * record</code> like <code>perf record, perf mem record, perf c2c record...</code> and so on.
  Is it possible to filter events (samples) for specific period?</p>