From owner-freebsd-current@freebsd.org Fri Aug 21 09:32:37 2015 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A6C979BE592 for ; Fri, 21 Aug 2015 09:32:37 +0000 (UTC) (envelope-from theraven@FreeBSD.org) Received: from theravensnest.org (theraven.freebsd.your.org [216.14.102.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "cloud.theravensnest.org", Issuer "StartCom Class 1 Primary Intermediate Server CA" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 779DD1983 for ; Fri, 21 Aug 2015 09:32:36 +0000 (UTC) (envelope-from theraven@FreeBSD.org) Received: from [192.168.0.7] (cpc16-cmbg15-2-0-cust60.5-4.cable.virginm.net [86.5.162.61]) (authenticated bits=0) by theravensnest.org (8.15.2/8.15.2) with ESMTPSA id t7L9WCJv019452 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 21 Aug 2015 09:32:15 GMT (envelope-from theraven@FreeBSD.org) X-Authentication-Warning: theravensnest.org: Host cpc16-cmbg15-2-0-cust60.5-4.cable.virginm.net [86.5.162.61] claimed to be [192.168.0.7] Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2102\)) Subject: Re: CPU Perf & Power Mgt From: David Chisnall In-Reply-To: Date: Fri, 21 Aug 2015 10:32:28 +0100 Cc: Will Green , FreeBSD Current Content-Transfer-Encoding: quoted-printable Message-Id: <11A9B382-005D-4551-A146-C19B8FCBB87A@FreeBSD.org> References: <7B1D7A3F-DA20-4195-8228-7D3F07790B5C@sundivenetworks.com> To: Justin Hibbits X-Mailer: Apple Mail (2.2102) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 21 Aug 2015 09:32:37 -0000 On 20 Aug 2015, at 17:44, Justin Hibbits wrote: >=20 > There was a working group at BSDCan this year on power management, and > what we need to / can do to bring it up to par with the modern world. > Unfortunately, I haven't had any time lately to work on it, but you > can read the notes at > https://wiki.freebsd.org/201506DevSummit/ClockDomains >=20 > In short, the goal is to add infrastructure to the kernel to support > overall power management of the system, scaling beyond cpufreq/powerd. > Looking for volunteers who could do some of this, due to my lack of > time to work on it. We also had a power management meeting at BSDCam this week. Robin = presented some slides (though the download seems to be broken for me at = the moment): = https://wiki.freebsd.org/201508DevSummit?action=3DAttachFile&do=3Dget&targ= et=3Dpower-management-for-freebsd-bsdcam-2015.pdf This includes the design that ARM is trying to push into Linux, which = looks like it would be adaptable to FreeBSD (and, on the plus side, our = complete lack of existing power management in the kernel already means = we don=E2=80=99t already have the legacy stuff that they are fighting in = Linux). The goal is to have the scheduler drive all of the (CPU) power = management. Any volunteers to work on this are welcome - ARM people are = happy to provide advice. David