From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hunt Subject: [PATCH] doc: add info on hyperthreading to power library Date: Wed, 31 Jan 2018 12:29:46 +0000 Message-ID: <1517401786-118971-1-git-send-email-david.hunt@intel.com> Cc: david.hunt@intel.com To: dev@dpdk.org Return-path: Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by dpdk.org (Postfix) with ESMTP id A95441B75C for ; Wed, 31 Jan 2018 13:29:59 +0100 (CET) List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Signed-off-by: David Hunt --- 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