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Elixir Cross Referencer

The following is an example of the vmstat.d script,


We run both vmstat.d and the original vmstat(1M) command at the same time
to compare outputs,

 $ vmstat 1
  kthr      memory            page            disk          faults      cpu
  r b w   swap  free  re  mf pi po fr de sr cd s0 -- --   in   sy   cs us sy id
  0 0 0 1147468 144324 2   8  2  1  1  0  0  1  0  0  0  294  990  355 18  2 80
  1 0 0 1065480 92276 13  73  0  0  0  0  0  0  0  0  0  359 1055  376 85 15  0
  0 0 0 1052088 82940  0   0  0  0  0  0  0  0  0  0  0  409  999  402 97  3  0
  0 0 0 1052088 82940  0   0  0  0  0  0  0  0  0  0  0  406  975  407 97  3  0
  0 0 0 1052088 82940  0   0  0  0  0  0  0  0  0  0  0  406 1037  429 97  3  0
  0 0 0 1052088 82940 247 1763 0 0  0  0  0  2  0  0  0  427 4828  680 81 19  0
  0 0 0 1051264 82300  0   0  0  0  0  0  0  0  0  0  0  414 1164  441 97  3  0
  0 0 0 1051264 82300 11 134  0  0  0  0  0  0  0  0  0  423 1218  461 95  5  0
  0 0 0 1051264 82300  0   0  0  0  0  0  0  0  0  0  0  416 1054  435 98  2  0
 [...]

 # ./vmstat.d
  w       swap     free   re    mf   pi   po   fr   sr    in    sy   cs
  0    1052088    82940    8    80    0    0    0    0   117   958  379
  0    1052088    82940    0     0    0    0    0    0   123   955  402
  0    1052088    82940    0     0    0    0    0    0   121  1025  420
  0    1052088    82940    0     0    0    0    0    0   121  1065  433
  0    1051264    82300 1008  7192    0    0    0    0   219  4886  684
  0    1051264    82300    0     0    0    0    0    0   193  1188  461
  0    1051264    82300   44   540    0    0    0    0   165  1226  450
  0    1051264    82300    0     0    0    0    0    0   123  1012  421
 [...]

Above we can see the columns are corresponding well. "re" and "mf" in the
DTrace output appear four times as large as they should be, because in the
DTrace output we are printing Kbs not page counts (for consistancy).

The DTrace output lacks the "summary since boot" line, as it is not using
Kstat to fetch this data.


The vmstat.d script is not intended itself as a useful program, rather it 
is intended as a starting point for other DTrace scripts; a starting point
of familiar statistics to provide the programmer with a "common ground"
of knowledge.