This change is required to allow the branch ratio algorithm to
power manage cores with no workload running on them. This is
useful both when idle cores don't use C-states and for a number of
hyperthreading scenarios.
---
examples/vm_power_manager/oob_monitor_x86.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/examples/vm_power_manager/oob_monitor_x86.c
b/examples/vm_power_manager/oob_monitor_x86.c
index 3c514475f..a5b1c168c 100644
--- a/examples/vm_power_manager/oob_monitor_x86.c
+++ b/examples/vm_power_manager/oob_monitor_x86.c
@@ -96,12 +96,12 @@ apply_policy(int core)
g_branch_misses = miss_diff;
if (hits_diff < (INTERVAL*100)) {
- /* Likely no workload running on this core. Skip. */
- return -1.0;
+ /* Likely no workload running on this core. */
+ ratio = 0.0;
+ } else {
+ ratio = (float)miss_diff * (float)100 / (float)hits_diff;
}
- ratio = (float)miss_diff * (float)100 / (float)hits_diff;
-
/*
* Store the last few directions that the ratio indicates
* we should take. If there's on 'up', then we scale up
--
2.17.1
