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    SubjectRe: High CPU load when machine is idle (related to PROBLEM: Unusually high load average when idle in 2.6.35, 2.6.35.1 and later)
    > > With 2.6.36-rc6, I'm seeing a load of around 0.60 when the machine
    > > is completely idle. This is similar to what someone reported for the
    > > latest 2.6.35.x stables. This is on a core i7 machine, but I've no
    > > time to bisect or test earlier versions right now, but I guess this
    > > is easy to reproduce on the same plateform.

    > After further investigation and cross-checking with the thread "PROBLEM:
    > Unusually high load average when idle in 2.6.35, 2.6.35.1 and later",
    > I came to the following results:

    > - the commit 74f5187ac873042f502227701ed1727e7c5fbfa9 isolated by Tim
    > seems to be the culprit;
    > - reverting it solves the problem with 2.6.36-rc7 in NOHZ mode: the load
    > when idle goes down to 0.00 (which it never does with the patch
    > applied)

    In fact, after several hours of uptime, I also came into a situation of
    the load being around 0.80 or 0.60 when idle with the commit reverted.
    So IMHO, just reverting is not a better option than keeping the
    offending commit, and a real rework of the code is needed to clean up
    the situation.

    Should'nt we enlarge the list of CC, because for now, responsivity has
    been close to 0 and it seems we will get a 2.6.36 with buggy load avg
    calculation. Even if it is only statistics, many supervision tools rely
    on the load avg, so for production environments, this is not a good
    thing.


    Best,
    --
    Damien


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