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    SubjectRE: Large increase in context switch rate
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    I'm talking about total number of context switches - kernbench gets it
    from

    time -f "%c" make -j 4

    Dividing through it gives me a rate of around 250/sec (vs Peters 3000),
    but I've set CONFIG_HZ=100 (vs Peters 1000), so they don't wildly
    conflict.

    Well spotted :-)

    - Alex


    -----Original Message-----
    From: Jeremy Fitzhardinge [mailto:jeremy@goop.org]
    Sent: 17 July 2008 16:45
    To: Alex Nixon (Intern)
    Cc: Peter Zijlstra; Ingo Molnar; Linux Kernel Mailing List; Ian Campbell
    Subject: Re: Large increase in context switch rate

    Alex Nixon (Intern) wrote:
    > Yeah I've checked - the number of context switches seems to be around
    > 60k regardless of whether CONFIG_PARAVIRT is switched on, and
    regardless
    > of whether it's running in domu or native (-j4 on dual core)
    >

    OK, just to be sure we're talking about the same thing, is kernbench
    displaying the context switch *rate*, or the total number of context
    switches during the build?

    Peter is looking at vmstat, which is showing cs/sec.

    J


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