diff mbox

[dpdk-dev] doc: add info on hyperthreading to power library

Message ID 1517401786-118971-1-git-send-email-david.hunt@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Thomas Monjalon
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Hunt, David Jan. 31, 2018, 12:29 p.m. UTC 
  Signed-off-by: David Hunt <david.hunt@intel.com>
---
 doc/guides/prog_guide/power_man.rst | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Kovacevic, Marko Feb. 6, 2018, 1:27 p.m. UTC | #1 
> Signed-off-by: David Hunt <david.hunt@intel.com>
> ---
>  doc/guides/prog_guide/power_man.rst | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/doc/guides/prog_guide/power_man.rst
> b/doc/guides/prog_guide/power_man.rst

<...>

Acked-by: Marko Kovacevic <marko.kovacevic@intel.com>
Thomas Monjalon Feb. 6, 2018, 8:32 p.m. UTC | #2 
06/02/2018 14:27, Kovacevic, Marko:
> > Signed-off-by: David Hunt <david.hunt@intel.com>
> > ---
> >  doc/guides/prog_guide/power_man.rst | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/doc/guides/prog_guide/power_man.rst
> > b/doc/guides/prog_guide/power_man.rst
> 
> <...>
> 
> Acked-by: Marko Kovacevic <marko.kovacevic@intel.com>

Applied, thanks
diff mbox

Patch

diff --git a/doc/guides/prog_guide/power_man.rst b/doc/guides/prog_guide/power_man.rst
index c5d62a3..fdf8f5f 100644
--- a/doc/guides/prog_guide/power_man.rst
+++ b/doc/guides/prog_guide/power_man.rst
@@ -97,6 +97,14 @@  basis. This is achieved by enabling Turbo Boost Technology in the BIOS, then
 looping through the relevant cores and enabling/disabling Turbo Boost on each
 core.
 
+Use of Power Library in a Hyper-Threaded Environment
+----------------------------------------------------
+
+In the case where the power library is in use on a system with Hyper-Threading enabled,
+the frequency on the physical core is set to the highest frequency of the Hyper-Thread siblings.
+So even though an application may request a scale down, the core frequency will
+remain at the highest frequency until all Hyper-Threads on that core request a scale down.
+
 API Overview of the Power Library
 ---------------------------------