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[Gurmeet <524281@xxxxxxxxxxxxxxxxxx>]

For the learned .....
Adding as a point to start with .. no guarantees  that this is the Saviour .... just a lead to who can get the heads and tails out of it 


# diff  -cp  tick-sched.c(2.6.37-rc4)   tick-sched.c(2.6.25-23)

...

*** tick.sched-2.6.37-rc4.c	2010-12-06 17:50:03.960025002 +0530
--- tick-sched-2.6.35-23.c	2010-11-18 03:45:19.000000000 +0530
*************** void tick_nohz_stop_sched_tick(int inidl
*** 405,411 ****
  		 * the scheduler tick in nohz_restart_sched_tick.
  		 */
  		if (!ts->tick_stopped) {
! 			select_nohz_load_balancer(1);
  
  			ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
  			ts->tick_stopped = 1;
--- 405,417 ----
  		 * the scheduler tick in nohz_restart_sched_tick.
  		 */
  		if (!ts->tick_stopped) {
! 			if (select_nohz_load_balancer(1)) {
! 				/*
! 				 * sched tick not stopped!
! 				 */
! 				cpumask_clear_cpu(cpu, nohz_cpu_mask);
! 				goto out;
! 			}
  
  			ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
  			ts->tick_stopped = 1;
*************** void tick_setup_sched_timer(void)
*** 774,779 ****
--- 780,786 ----
  {
  	struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
  	ktime_t now = ktime_get();
+ 	u64 offset;
  
  	/*
  	 * Emulate tick processing via per-CPU hrtimers:
*************** void tick_setup_sched_timer(void)
*** 783,788 ****
--- 790,799 ----
  
  	/* Get the next period (per cpu) */
  	hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update());
+ 	offset = ktime_to_ns(tick_period) >> 1;
+ 	do_div(offset, num_possible_cpus());
+ 	offset *= smp_processor_id();
+ 	hrtimer_add_expires_ns(&ts->sched_timer, offset);
  
  	for (;;) {
  		hrtimer_forward(&ts->sched_timer, now, tick_period);

-- 
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https://bugs.launchpad.net/bugs/524281

Title:
  Tens of wakes per second in "[kernel scheduler] Load balancing tick" on Core 2 Duo even with only 1 core enabled