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    SubjectRe: UP 2.2.18 makes kernels 3% faster than UP 2.4.0-test12
    Helge Hafting wrote:
    >Steven Cole wrote:
    >[...]
    >>Simple question here, and risking displaying great ignorance:
    >>Does it make sense to use make -jN where N is much greater than the
    >>number of CPUs?
    >
    >No, but it makes sense to have N at least one more than the number of
    >cpus,
    >if you have the memory. This because your processes occationally
    >will wait for disk io, and this time may then be utilized to
    >run the "extra" task. But don't overdo it, as you get less disk
    >cache this way. make -j3 seems to be fastest on my 2-cpu machine
    >with 128M ram.

    Thanks for the answer. That makes a lot of sense. When I get the time,
    I'll verify that, at least for this fairly narrowly defined task of building
    a kernel.

    In order to minimize external and variable influences on the CPU load, I
    performed all these tests in console mode not connected to a network. That
    may have been an unrealistic test, as that is not how I normally do kernel
    builds. Having to juggle more work, like running X and KDE, could shift the
    results (2.2.18 vs 2.4.0-test12) around a bit. I'll repeat the tests with a
    more normal work environment. If anything statistically significant is found,
    I'll mention it. Thanks to all for their input.

    Steven
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