Re: [PATCH 4/13] find_busiest_group fixlets
* Nick Piggin <[EMAIL PROTECTED]> wrote: > 4/13 > 5/13 #insert Acked-by: Ingo Molnar <[EMAIL PROTECTED]> Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 4/13] find_busiest_group fixlets
* Nick Piggin [EMAIL PROTECTED] wrote: 4/13 5/13 #insert previous mail Acked-by: Ingo Molnar [EMAIL PROTECTED] Ingo - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 4/13] find_busiest_group fixlets
4/13
Fix up a few small warts in the periodic multiprocessor rebalancing
code.
Signed-off-by: Nick Piggin <[EMAIL PROTECTED]>
Index: linux-2.6/kernel/sched.c
===
--- linux-2.6.orig/kernel/sched.c 2005-02-24 17:31:28.431609701 +1100
+++ linux-2.6/kernel/sched.c 2005-02-24 17:43:38.806447240 +1100
@@ -1830,13 +1830,12 @@
* by pulling tasks to us. Be careful of negative numbers as they'll
* appear as very large values with unsigned longs.
*/
- *imbalance = min(max_load - avg_load, avg_load - this_load);
-
/* How much load to actually move to equalise the imbalance */
- *imbalance = (*imbalance * min(busiest->cpu_power, this->cpu_power))
-/ SCHED_LOAD_SCALE;
+ *imbalance = min((max_load - avg_load) * busiest->cpu_power,
+(avg_load - this_load) * this->cpu_power)
+ / SCHED_LOAD_SCALE;
- if (*imbalance < SCHED_LOAD_SCALE - 1) {
+ if (*imbalance < SCHED_LOAD_SCALE) {
unsigned long pwr_now = 0, pwr_move = 0;
unsigned long tmp;
@@ -1862,14 +1861,16 @@
max_load - tmp);
/* Amount of load we'd add */
- tmp = SCHED_LOAD_SCALE*SCHED_LOAD_SCALE/this->cpu_power;
- if (max_load < tmp)
- tmp = max_load;
+ if (max_load*busiest->cpu_power <
+SCHED_LOAD_SCALE*SCHED_LOAD_SCALE)
+ tmp = max_load*busiest->cpu_power/this->cpu_power;
+ else
+ tmp = SCHED_LOAD_SCALE*SCHED_LOAD_SCALE/this->cpu_power;
pwr_move += this->cpu_power*min(SCHED_LOAD_SCALE, this_load + tmp);
pwr_move /= SCHED_LOAD_SCALE;
- /* Move if we gain another 8th of a CPU worth of throughput */
- if (pwr_move < pwr_now + SCHED_LOAD_SCALE / 8)
+ /* Move if we gain throughput */
+ if (pwr_move <= pwr_now)
goto out_balanced;
*imbalance = 1;
@@ -1877,7 +1878,7 @@
}
/* Get rid of the scaling factor, rounding down as we divide */
- *imbalance = (*imbalance + 1) / SCHED_LOAD_SCALE;
+ *imbalance = *imbalance / SCHED_LOAD_SCALE;
return busiest;
[PATCH 4/13] find_busiest_group fixlets
4/13
Fix up a few small warts in the periodic multiprocessor rebalancing
code.
Signed-off-by: Nick Piggin [EMAIL PROTECTED]
Index: linux-2.6/kernel/sched.c
===
--- linux-2.6.orig/kernel/sched.c 2005-02-24 17:31:28.431609701 +1100
+++ linux-2.6/kernel/sched.c 2005-02-24 17:43:38.806447240 +1100
@@ -1830,13 +1830,12 @@
* by pulling tasks to us. Be careful of negative numbers as they'll
* appear as very large values with unsigned longs.
*/
- *imbalance = min(max_load - avg_load, avg_load - this_load);
-
/* How much load to actually move to equalise the imbalance */
- *imbalance = (*imbalance * min(busiest-cpu_power, this-cpu_power))
-/ SCHED_LOAD_SCALE;
+ *imbalance = min((max_load - avg_load) * busiest-cpu_power,
+(avg_load - this_load) * this-cpu_power)
+ / SCHED_LOAD_SCALE;
- if (*imbalance SCHED_LOAD_SCALE - 1) {
+ if (*imbalance SCHED_LOAD_SCALE) {
unsigned long pwr_now = 0, pwr_move = 0;
unsigned long tmp;
@@ -1862,14 +1861,16 @@
max_load - tmp);
/* Amount of load we'd add */
- tmp = SCHED_LOAD_SCALE*SCHED_LOAD_SCALE/this-cpu_power;
- if (max_load tmp)
- tmp = max_load;
+ if (max_load*busiest-cpu_power
+SCHED_LOAD_SCALE*SCHED_LOAD_SCALE)
+ tmp = max_load*busiest-cpu_power/this-cpu_power;
+ else
+ tmp = SCHED_LOAD_SCALE*SCHED_LOAD_SCALE/this-cpu_power;
pwr_move += this-cpu_power*min(SCHED_LOAD_SCALE, this_load + tmp);
pwr_move /= SCHED_LOAD_SCALE;
- /* Move if we gain another 8th of a CPU worth of throughput */
- if (pwr_move pwr_now + SCHED_LOAD_SCALE / 8)
+ /* Move if we gain throughput */
+ if (pwr_move = pwr_now)
goto out_balanced;
*imbalance = 1;
@@ -1877,7 +1878,7 @@
}
/* Get rid of the scaling factor, rounding down as we divide */
- *imbalance = (*imbalance + 1) / SCHED_LOAD_SCALE;
+ *imbalance = *imbalance / SCHED_LOAD_SCALE;
return busiest;
