| | 1 | /* |
| | 2 | * Only give sleepers 50% of their service deficit. This allows |
| | 3 | * them to run sooner, but does not allow tons of sleepers to |
| | 4 | * rip the spread apart. |
| | 5 | */ |
| | 6 | SCHED_FEAT(GENTLE_FAIR_SLEEPERS, 1) |
| | 7 | |
| | 8 | /* |
| | 9 | * Place new tasks ahead so that they do not starve already running |
| | 10 | * tasks |
| | 11 | */ |
| | 12 | SCHED_FEAT(START_DEBIT, 1) |
| | 13 | |
| | 14 | /* |
| | 15 | * Should wakeups try to preempt running tasks. |
| | 16 | */ |
| | 17 | SCHED_FEAT(WAKEUP_PREEMPT, 1) |
| | 18 | |
| | 19 | /* |
| | 20 | * Based on load and program behaviour, see if it makes sense to place |
| | 21 | * a newly woken task on the same cpu as the task that woke it -- |
| | 22 | * improve cache locality. Typically used with SYNC wakeups as |
| | 23 | * generated by pipes and the like, see also SYNC_WAKEUPS. |
| | 24 | */ |
| | 25 | SCHED_FEAT(AFFINE_WAKEUPS, 1) |
| | 26 | |
| | 27 | /* |
| | 28 | * Prefer to schedule the task we woke last (assuming it failed |
| | 29 | * wakeup-preemption), since its likely going to consume data we |
| | 30 | * touched, increases cache locality. |
| | 31 | */ |
| | 32 | SCHED_FEAT(NEXT_BUDDY, 0) |
| | 33 | |
| | 34 | /* |
| | 35 | * Prefer to schedule the task that ran last (when we did |
| | 36 | * wake-preempt) as that likely will touch the same data, increases |
| | 37 | * cache locality. |
| | 38 | */ |
| | 39 | SCHED_FEAT(LAST_BUDDY, 1) |
| | 40 | |
| | 41 | /* |
| | 42 | * Consider buddies to be cache hot, decreases the likelyness of a |
| | 43 | * cache buddy being migrated away, increases cache locality. |
| | 44 | */ |
| | 45 | SCHED_FEAT(CACHE_HOT_BUDDY, 1) |
| | 46 | |
| | 47 | /* |
| | 48 | * Use arch dependent cpu power functions |
| | 49 | */ |
| | 50 | SCHED_FEAT(ARCH_POWER, 0) |
| | 51 | |
| | 52 | SCHED_FEAT(HRTICK, 0) |
| | 53 | SCHED_FEAT(DOUBLE_TICK, 0) |
| | 54 | SCHED_FEAT(LB_BIAS, 1) |
| | 55 | SCHED_FEAT(LB_SHARES_UPDATE, 1) |
| | 56 | SCHED_FEAT(ASYM_EFF_LOAD, 1) |
| | 57 | |
| | 58 | /* |
| | 59 | * Spin-wait on mutex acquisition when the mutex owner is running on |
| | 60 | * another cpu -- assumes that when the owner is running, it will soon |
| | 61 | * release the lock. Decreases scheduling overhead. |
| | 62 | */ |
| | 63 | SCHED_FEAT(OWNER_SPIN, 1) |
| | 64 | |
| | 65 | /* |
| | 66 | * Decrement CPU power based on irq activity |
| | 67 | */ |
| | 68 | SCHED_FEAT(NONIRQ_POWER, 1) |
git://bbs.cooldavid.org / net-next-2.6.git / blame_incremental