DPDK patches and discussions
 help / color / mirror / Atom feed
From: David Hunt <david.hunt@intel.com>
To: dev@dpdk.org
Cc: david.hunt@intel.com
Subject: [dpdk-dev] [PATCH] doc: add info on hyperthreading to power library
Date: Wed, 31 Jan 2018 12:29:46 +0000	[thread overview]
Message-ID: <1517401786-118971-1-git-send-email-david.hunt@intel.com> (raw)

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
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
 ---------------------------------
 
-- 
2.7.4

             reply	other threads:[~2018-01-31 12:29 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-31 12:29 David Hunt [this message]
2018-02-06 13:27 ` Kovacevic, Marko
2018-02-06 20:32   ` Thomas Monjalon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1517401786-118971-1-git-send-email-david.hunt@intel.com \
    --to=david.hunt@intel.com \
    --cc=dev@dpdk.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).