On SMP, CPU usage runs backwards?

From: Albert D. Cahalan (acahalan@cs.uml.edu)
Date: Sun Jun 18 2000 - 23:11:10 EST


The test program below gives some odd results for SMP systems.
While running it, be sure to load down the system with CPU hogs.
For the cases shown below, ticks of idle time decrease.

CPU states: 1.6% user, 88.3% system, 0.0% nice, 10.0% idle
CPU states: 0.0% user, 76.5% system, 0.0% nice, 23.4% idle
CPU states: 8.3% user, 91.6% system, 0.0% nice, 0.0% idle
  The clock runs backwards!!!!! The last lines were:
  cpu 1257905 31724 8218879 588775820
  cpu 1257905 31724 8218930 588775817
CPU states: 0.0% user, 106.2% system, 0.0% nice, 8947842.2% idle
  That was over 1000. The last lines were:
  cpu 1257905 31724 8218879 588775820
  cpu 1257905 31724 8218930 588775817
CPU states: 1.3% user, 93.4% system, 0.0% nice, 5.2% idle
CPU states: 3.3% user, 90.0% system, 0.0% nice, 6.6% idle
CPU states: 1.6% user, 96.6% system, 0.0% nice, 1.6% idle
  The clock runs backwards!!!!! The last lines were:
  cpu 1257909 31724 8219113 588775826
  cpu 1257910 31724 8219162 588775824

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ELU/:;F?C,_Q/P?#>'^'%'+8<_Y.8J3)[ZQ$;[W\D,%!2E@X`````
`
end

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