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Today a application that I have crashed. I went to check why and is because a new field in /proc/stat:

cpu  635570 3943 1264332 13562455 65965 80 4806 0 0 0
cpu0 311689 2102 654770 6755602 32431 38 4127 0 0 0
cpu1 323881 1840 609562 6806853 33534 41 678 0 0 0 

The last 0 is undocumented, at least in the man page. Does anyone know what is it?

I'm running now in Ubuntu 12.04, and before in 10.04.

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up vote 2 down vote accepted

The documentation hasn't been updated together with the code. You can find out what the new field is in the source code. Field #9 is the time spent running in guest virtual machines hosted by this system; field #10 is the time spent in guests with low priority (#10 is to #9 as #2 is to #1).

As a general design note, when there are multiple fields like this, never assume that the total number of fields is fixed. Ignore any extra field.

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thanks very much :) – Pedro Dusso May 15 '12 at 23:59

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