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Description of problem:
All CPU counters in /proc/stat should be ever increasing (until they wrap, at
least) but, on some systems with the kernel version above,
the idle counter can go up and down by one:

# while : ; do grep cpu0 /proc/stat; sleep 5; done
cpu0 899789 34080527 878200 275371855
cpu0 899794 34081013 878210 275371855
cpu0 899801 34081500 878217 275371855
cpu0 899807 34081986 878226 275371854
cpu0 899815 34082473 878232 275371855
cpu0 899823 34082959 878238 275371855
cpu0 899830 34083445 878247 275371855

This happens when the CPU is 100% busy. To force this condition, a simple loop
will do:

# while : ; do : ; done


This can also happen on MP systems. It confuses performance tools.

Version-Release number of selected component (if applicable):
kernel-2.4.18-14 #1 Wed Sep 4 13:35:50 EDT 2002

How reproducible:
Sometimes

Steps to Reproduce:
1. while : ; do : ; done & 
2. while : ; do grep cpu0 /proc/stat; sleep 5; done
3.
    

Actual Results:  Idle counter goes up and down by one.

Expected Results:  Idle counter or any other counter should never go down.

Additional info: