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    SubjectRe: Schedule idle
    David Feuer <> writes:

    > Why is this better than nice-19?

    It totally removes the job from the OS's run queue, so it takes _no_ CPU
    time when the load crosses a threshold. When the load drops below a second
    threshold, it puts it back on. So, if your loadwatched job holds the load
    at 1.0 normally, you set the highpoint for something like 1.15. When
    anything significant starts, the load goes over 1.15, and the loadwatched
    job totally stops (with SIGSTOP). Whatever loaded the system will
    presumably now keep the load over the second point, say 0.15, and it will
    not have the loadwatched job stealing any cycles from it. Once the load
    drops below 0.15, the loadwatched job is sent a SIGCONT.

    As mentioned elsewhere in this thread, a nice 19 job still gets 5% of the
    CPU. And, if that job is using resources like lots of memory or doing I/O,
    it can have a disproportional impact on the system. Even for a CPU bound
    job like rc5des, some people can notice it running at nice 19 because of
    slightly slower interactive performance. If you're one of them, loadwatch
    works pretty nicely for getting rid of that small lag.

    +-------------------- finger for pgp public key ---------------------+
    | Dale E. Martin | Clifton Labs, Inc. | Senior Computer Engineer |
    | | |

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