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* Peter Williams <peterw@aurema.com> wrote: > -- at the end of each time slice (or when waking up) each task is > given a complete new time slice and, if class SCHED_NORMAL, is put in > a priority slot given by (static_prio + MAX_BONUS - interactive_bonus) this is the Achilles' heel of approaches that try to get rid of the active/expired array and/or try to get rid of timeslice tracking. A CPU-bound task which schedules away for small amounts of time will get a disproportionatly larger share of the CPU than a CPU-bound task that doesnt schedule at all. just try it - run a task that runs 95% of the time and sleeps 5% of the time, and run a (same prio) task that runs 100% of the time. With the current scheduler the slightly-sleeping task gets 45% of the CPU, the looping one gets 55% of the CPU. With your patch the slightly-sleeping process can easily monopolize 90% of the CPU! Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
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