From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Alexander E. Patrakov" Subject: Re: [REANNOUNCE] Audio Mini Summit 2015, 8th October, Dublin Date: Tue, 14 Jul 2015 22:05:34 +0500 Message-ID: <55A5415E.90407@gmail.com> References: <20150714150352.GW11162@sirena.org.uk> <55A5330E.7000604@gmail.com> <20150714161711.GB11162@sirena.org.uk> <55A53A7B.20806@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wg0-f48.google.com (mail-wg0-f48.google.com [74.125.82.48]) by alsa0.perex.cz (Postfix) with ESMTP id BF5692652B0 for ; Tue, 14 Jul 2015 19:05:36 +0200 (CEST) Received: by wgjx7 with SMTP id x7so13804840wgj.2 for ; Tue, 14 Jul 2015 10:05:36 -0700 (PDT) In-Reply-To: <55A53A7B.20806@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Mark Brown Cc: Takashi Iwai , alsa-devel@alsa-project.org, Liam Girdwood List-Id: alsa-devel@alsa-project.org 14.07.2015 21:36, Alexander E. Patrakov wrote: > 14.07.2015 21:17, Mark Brown wrote: >> On Tue, Jul 14, 2015 at 09:04:30PM +0500, Alexander E. Patrakov wrote: >> >>> I would like to see some direct measurements related to recent >>> power-saving >>> proposals, including the "disable rewinds" flag. Myself, I can redo >>> battery-life measurements on Intel-based laptops that my colleagues >>> have, >>> and maybe compare dmix, PulseAudio and CRAS in terms of power >>> consumption. >> >> The numbers I seem to remember seeing at the time were these IIRC: >> >> >> http://linux-tipps.blogspot.co.uk/2011/04/power-performance-of-pulseaudio-alsa.html >> >> >> saying there was a 0.4W win (I think Arun had some similar numbers). > > Thanks for the link. I have no reason to doubt these measurements. Note, > however, that they are of the "pulseaudio vs pulseaudio" type, and give > no insight into the structure of the win. Oops, sorry for misreading the blog post. It's actually "alsa vs pulseaudio vs high-latency pulseaudio", and does prove that, on the reporter's hardware, the win is not related to userspace inefficiency. -- Alexander E. Patrakov