On big POWER7 boxes we see large amounts of CPU time in system
processes like workqueue and watchdog kernel threads.

We currently rebalance the entire machine each time a task goes
idle and this is very expensive on large machines. Disable newidle
balancing at the node level and rely on the scheduler tick to
rebalance across nodes.

Signed-off-by: Anton Blanchard <an...@samba.org>
---

Index: linux-2.6-work/arch/powerpc/include/asm/topology.h
===================================================================
--- linux-2.6-work.orig/arch/powerpc/include/asm/topology.h     2011-07-25 
12:14:25.448671947 +1000
+++ linux-2.6-work/arch/powerpc/include/asm/topology.h  2011-07-25 
12:14:26.568692651 +1000
@@ -75,7 +75,7 @@ static inline int pcibus_to_node(struct
        .forkexec_idx           = 0,                                    \
                                                                        \
        .flags                  = 1*SD_LOAD_BALANCE                     \
-                               | 1*SD_BALANCE_NEWIDLE                  \
+                               | 0*SD_BALANCE_NEWIDLE                  \
                                | 1*SD_BALANCE_EXEC                     \
                                | 1*SD_BALANCE_FORK                     \
                                | 0*SD_BALANCE_WAKE                     \


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