doc: add power management scale mode reaction time note

When using PMD Power Management, scale mode reacts slower than
monitor mode and pause mode. Add note in user guide to this
effect.

Signed-off-by: David Hunt <david.hunt@intel.com>

diff --git a/doc/guides/prog_guide/power_man.rst b/doc/guides/prog_guide/power_man.rst
index e387d7811e13eb7170c75d47ac50dca026375886..4484a94dc8c90f5f956170a631762613da0b1d09 100644 (file)
--- a/doc/guides/prog_guide/power_man.rst
+++ b/doc/guides/prog_guide/power_man.rst
@@ -217,6 +217,8 @@ power saving whenever empty poll count reaches a certain number.
 * Frequency scaling
    This power saving scheme will use ``librte_power`` library functionality to
    scale the core frequency up/down depending on traffic volume.
+   The reaction time of the frequency scaling mode is longer
+   than the pause and monitor mode.
 
 The "monitor" mode is only supported in the following configurations and scenarios:
 

diff --git a/doc/guides/sample_app_ug/l3_forward_power_man.rst b/doc/guides/sample_app_ug/l3_forward_power_man.rst
index 8817eaadbfc3bee170b3309c03694bfb3ceeef45..2e350c45f1faf08ad0e62662789831a20b751540 100644 (file)
--- a/doc/guides/sample_app_ug/l3_forward_power_man.rst
+++ b/doc/guides/sample_app_ug/l3_forward_power_man.rst
@@ -347,6 +347,8 @@ and has three available power management schemes:
 ``scale``
   This will use frequency scaling routines
   available in the ``librte_power`` library.
+  The reaction time of the scale mode is longer
+  than the pause and monitor mode.
 
 See :doc:`Power Management<../prog_guide/power_man>` chapter
 in the DPDK Programmer's Guide for more details on PMD power management.