Re: [PATCH] Remove timer frequency choice if tickless is enabled - Kernel

This is a discussion on Re: [PATCH] Remove timer frequency choice if tickless is enabled - Kernel ; (lkml Cc:-ed) * Carlos R. Mafra wrote: > choice > prompt "Timer frequency" > + depends on !NO_HZ > default HZ_250 > help > Allows the configuration of the timer frequency. It is customary we are not there yet to ...

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Thread: Re: [PATCH] Remove timer frequency choice if tickless is enabled

  1. Re: [PATCH] Remove timer frequency choice if tickless is enabled


    (lkml Cc:-ed)

    * Carlos R. Mafra wrote:

    > choice
    > prompt "Timer frequency"
    > + depends on !NO_HZ
    > default HZ_250
    > help
    > Allows the configuration of the timer frequency. It is customary


    we are not there yet to be able to do this. With NO_HZ the tick is only
    disabled when we go idle - but it still runs (and we rely on it, for
    example in the scheduler code) while we are non-idle. Peter Zijlstra is
    working on the 'high-res scheduler tick' feature to remove the scheduler
    dependencies.

    Ingo
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  2. Re: [PATCH] Remove timer frequency choice if tickless is enabled


    On Mon, 2008-01-14 at 09:25 +0100, Ingo Molnar wrote:
    > (lkml Cc:-ed)
    >
    > * Carlos R. Mafra wrote:
    >
    > > choice
    > > prompt "Timer frequency"
    > > + depends on !NO_HZ
    > > default HZ_250
    > > help
    > > Allows the configuration of the timer frequency. It is customary

    >
    > we are not there yet to be able to do this. With NO_HZ the tick is only
    > disabled when we go idle - but it still runs (and we rely on it, for
    > example in the scheduler code) while we are non-idle. Peter Zijlstra is
    > working on the 'high-res scheduler tick' feature to remove the scheduler
    > dependencies.


    Yes, and even then we're still not there, there are various other
    features that are tick driven, among them the RCU quiecent state
    machine.

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