lkml.org 
[lkml]   [2009]   [Aug]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 0/3] cpu: idle state framework for offline CPUs.
    Hi,

    On Wed, Aug 05, 2009 at 10:25:53PM +0800, Gautham R Shenoy wrote:
    > In this patch-series, we propose to extend the CPU-Hotplug infrastructure
    > and allow the system administrator to choose the desired state the CPU should
    > go to when it is offlined. We think this approach addresses the concerns about
    > determinism as well as transparency, since CPU-Hotplug already provides
    > notification mechanism which the userspace can listen to for any change
    > in the configuration and correspondingly readjust any previously set
    > cpu-affinities.
    Peter dislikes any approach (including cpuhotplug) which breaks userspace policy,
    even userspace can get a notification.

    > Also, approaches such as [1] can make use of this
    > extended infrastructure instead of putting the CPU to an arbitrary C-state
    > when it is offlined, thereby providing the system administrator a rope to hang
    > himself with should he feel the need to do so.
    I didn't see the reason why administrator needs to know which state offline cpu
    should stay. Don't know about powerpc side, but in x86 side, it appears deepest
    C-state is already preferred.

    Thanks,
    Shaohua


    \
     
     \ /
      Last update: 2009-08-06 04:01    [from the cache]
    ©2003-2014 Jasper Spaans. hosted at Digital Ocean