[PATCH 4/5] powerpc/numa: Disable NEWIDLE balancing at node level
From: Anton Blanchard <hidden>
Date: 2011-07-25 12:37:57
Also in:
lkml
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 <redacted> --- 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 \