From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Jones Subject: Re: about cpufreq on intel dual core processor Date: Wed, 22 Aug 2007 20:18:15 -0400 Message-ID: <20070823001815.GD18739@redhat.com> References: <193428.18959.qm@web39710.mail.mud.yahoo.com> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <193428.18959.qm@web39710.mail.mud.yahoo.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=m.gmane.org+glkc-cpufreq=m.gmane.org@lists.linux.org.uk Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: M C Cc: cpufreq@lists.linux.org.uk On Sat, Aug 18, 2007 at 07:54:01AM -0700, M C wrote: > Hi, I have a simple question about cpufreq on intel dualcore processor. > > if each core has six frequency levels, then should i change the frequency levels for both of the cores simultaneously or i can change them separately? > > because the processor supports hyper threading techonogy, so there are fours cores in the linux system. then how should i treat the four cpu when i want to do the frequency scaling? You are able to set different frequencies per core, however you only save power per-socket, so unless they're all ramped down, you won't be lowering the voltage of the socket if one core keeps the package busy. Dave -- http://www.codemonkey.org.uk