Explain influence of per-core P-states and hyper threading on the
effective performance.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
Documentation/admin-guide/pm/intel_pstate.rst | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst
index ac6f5c597a56..ec0f7c111f65 100644
--- a/Documentation/admin-guide/pm/intel_pstate.rst
+++ b/Documentation/admin-guide/pm/intel_pstate.rst
@@ -495,7 +495,15 @@ on the following rules, regardless of the current operation mode of the driver:
2. Each individual CPU is affected by its own per-policy limits (that is, it
cannot be requested to run faster than its own per-policy maximum and it
- cannot be requested to run slower than its own per-policy minimum).
+ cannot be requested to run slower than its own per-policy minimum). The
+ effective performance depends on whether the platform supports per core
+ P-states, hyper-threading is enabled and on current performance requests
+ from other CPUs. When platform doesn't support per core P-states, the
+ effective performance can be more than the policy limits set on a CPU, if
+ other CPUs are requesting higher performance at that moment. Even with per
+ core P-states support, when hyper-threading is enabled, if the sibling CPU
+ is requesting higher performance, the other siblings will get higher
+ performance than their policy limits.
3. The global and per-policy limits can be set independently.
--
2.17.1
