Messages in this thread | ![/](/images/icornerl.gif) | | Date | Fri, 23 Oct 2015 07:49:51 +0530 | From | Viresh Kumar <> | Subject | Re: [PATCH] timer: Lazily wakup nohz CPU when adding new timer. |
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On 22-10-15, 14:40, Yunhong Jiang wrote: > A naive question is, why it's sure a tick will happen when the tickless > processor is in idle?
How do you get this impression? I don't think anyone has said that.
We are talking about deferrable timers, which by design are only required if the target CPU is not-idle. If it is idle, then the timer isn't required to be serviced until the CPU wakes up. And the CPU can take whatever time it wants to wake up again.
> Is it because scheduler load balance is sure to send a > tick to the processor in future?
No. We aren't expecting the CPU to wake up any time soon. Just ignore the deferrable timer.
-- viresh
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