title: How to interpret Papi output
body: <p>I have collected data of Number of L2 cache misses using PAPI. I had run an MPI application with 4 threads (mpirun -np 4) and each thread reads the cache misses in L2. Each thread outputs data for every timestamp. 
  eg:</p>
  
  <pre><code>Timestamp              data
  xxx530     thread# 0   2136
  xxx531     thread# 0   3217
  ..           .          .
  .            .          . 
  .            .          .
  .            .          .
  xxx550      thread# 0   412334255
  
  xxx530      thread #1    2456
  xxx531      thread#1     4243
  xxx532      thread #1    4567 
  and so on
  </code></pre>
  
  <p>Now my qstn , is whether i shud add all the cache miss values at time stamp xxx530 for thread 0,1, 2 and 3 OR shud i take the max-value for thrreda0,1,2,3 for timestamp xxx530 ?</p>