• Peter Zijlstra's avatar
    sched: Stop buddies from hogging the system · de69a80b
    Peter Zijlstra authored
    Clear buddies more agressively.
    
    The (theoretical, haven't actually observed any of this) problem is
    that when we do not select either buddy in pick_next_entity()
    because they are too far ahead of the left-most task, we do not
    clear the buddies.
    
    This means that as soon as we service the left-most task, these
    same buddies will be tried again on the next schedule. Now if the
    left-most task was a pure hog, it wouldn't have done any wakeups
    and it wouldn't have set buddies of its own. That leads to the old
    buddies dominating, which would lead to bad latencies.
    Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
    Cc: Mike Galbraith <efault@gmx.de>
    LKML-Reference: <new-submission>
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    de69a80b
sched_fair.c 46.8 KB