Re: HT and idle = poll

John Levon (
Thu, 6 Mar 2003 23:59:04 +0000

On Thu, Mar 06, 2003 at 02:22:48PM -0800, Martin J. Bligh wrote:

> BTW, could someone give a brief summary of why idle=poll is needed for
> oprofile, I'd love to add it do the "documentation for dummies" file I
> was writing.

Because events like CPU_CLK_UNHALTED don't tick when the cpu is halted,
so the idle time doesn't show up properly in the kernel profile.
idle=poll doesn't hlt so the profile for poll_idle() reflects the actual
idle percentage.

Something like that anyway.

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