1. 17 3月, 2008 16 次提交
  2. 16 3月, 2008 21 次提交
  3. 15 3月, 2008 3 次提交
    • I
      sched: simplify sched_slice() · 6a6029b8
      Ingo Molnar 提交于
      Use the existing calc_delta_mine() calculation for sched_slice(). This
      saves a divide and simplifies the code because we share it with the
      other /cfs_rq->load users.
      
      It also improves code size:
      
            text    data     bss     dec     hex filename
           42659    2740     144   45543    b1e7 sched.o.before
           42093    2740     144   44977    afb1 sched.o.after
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      6a6029b8
    • I
      sched: fix fair sleepers · e22ecef1
      Ingo Molnar 提交于
      Fair sleepers need to scale their latency target down by runqueue
      weight. Otherwise busy systems will gain ever larger sleep bonus.
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      e22ecef1
    • P
      sched: fix overload performance: buddy wakeups · aa2ac252
      Peter Zijlstra 提交于
      Currently we schedule to the leftmost task in the runqueue. When the
      runtimes are very short because of some server/client ping-pong,
      especially in over-saturated workloads, this will cycle through all
      tasks trashing the cache.
      
      Reduce cache trashing by keeping dependent tasks together by running
      newly woken tasks first. However, by not running the leftmost task first
      we could starve tasks because the wakee can gain unlimited runtime.
      
      Therefore we only run the wakee if its within a small
      (wakeup_granularity) window of the leftmost task. This preserves
      fairness, but does alternate server/client task groups.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      aa2ac252