Re: [3.2.16 -> 3.2.17 regression] High reported CPU load when idle

From: Anders Boström
Date: Wed May 30 2012 - 11:04:30 EST


>>>>> "DS" == Doug Smythies <dsmythies@xxxxxxxxx> writes:

DS> This statement: "Starting with 3.2.17-1, the CPU load accounting is broken when the computer is idle. The CPU load is reported as >0.50 when idle. 3.2.16-1 don't suffer from this problem."
DS> In my opinion has the following mistakes:
DS> . The computer is not actually idle. If it was actually idle the reported load average would be 0.

Well, I tested in single user mode, with very few processes running,
mostly init, getty, bash and top (+ a lot of kernel threads). And
3.2.17 reported a load of >0.5 . Under the same conditions 3.2.16
typically reports 0.01 or 0.00 .

DS> . Yes, the new kernel reported load average is high, as detailed in the PNG file or the web notes.
DS> . The older kernel suffers from a different problem, under all other conditions being the same, the reported load average would have been too low.

I don't know if 0.01 is *too* low, but it should be much closer to the
truth than >0.5.

/ Anders
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