From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40708) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e1Qwx-0004eo-7G for qemu-devel@nongnu.org; Mon, 09 Oct 2017 01:50:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e1Qwt-0002dP-Ux for qemu-devel@nongnu.org; Mon, 09 Oct 2017 01:49:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53912) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e1Qwt-0002cT-Mh for qemu-devel@nongnu.org; Mon, 09 Oct 2017 01:49:55 -0400 From: Markus Armbruster References: Date: Mon, 09 Oct 2017 07:49:50 +0200 In-Reply-To: (Zir Blazer's message of "Sat, 7 Oct 2017 02:58:55 +0000") Message-ID: <87376suayp.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] What is the status of the QEMU sound rework? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Zir Blazer Cc: "qemu-devel@nongnu.org" , Gerd Hoffmann Copying Gerd... Zir Blazer writes: > I'm a VGA Passthrough user that uses a QEMU VM to fully replace a Windows= native install as the main OS. > > > Currently, one of the biggest hazzles for many users is that sound is har= d to get working properly with the emulated AC'97 and Intel HDA Sound Cards= due to crackle or latency issues (Latency issues heavily affects recording= scenarios, like voice chat applications in a VM). An example here, through= there are far more: https://www.reddit.com/r/VFIO/comments/746t4h/getting_= rid_of_audio_crackling_once_and_for_all/ > > > Some people managed to get sound working at acceptable levels by meddling= with the environmental variables, but most of the solutions come from a tr= ial-and-error esoteric procedure instead of structured troubleshooting, as = each user has to figure out which settings makes the emulated Sound Cards w= ork decently in his system. For those that failed getting the desired resul= ts with emulation, they have to throw Hardware at the issue by using PCI Pa= ssthrough of a Sound Card, or an USB Sound Card via USB Passthrough (Or eve= n have it plugged to an USB Controller passed to the VM via PCI Passthrough= ), or using the passthroughed Video Card HDMI with a Monitor with speakers,= just to solve the sound issues. The problem is that this complicates this = type of setups a lot, and it makes impossible a typical use case that would= be that all the VMs output the sound to the host, which has control of the= Motherboard integrated Sound Card, and it mixes it to use a single set of = speakers for the entire system. > > > > I have been googling around and found that at several times, there were i= deas and proposal, and even some code, that were intended to overhaul QEMU = sound system. Examples includes: > > GSoC 2011 Xen PV Audio, a paravirtualized Sound Card https://wiki.xenproj= ect.org/wiki/Archived/GSoc_2011_Ideas > GSoC 2015 QEMU rework of the sound environmental variables https://wiki.q= emu.org/Google_Summer_of_Code_2015#QEMU_audio_backend > GSoC 2017 QEMU rework a patch series that did precisely that https://wiki= .qemu.org/Google_Summer_of_Code_2017#QEMU_audio_backend > https://lists.nongnu.org/archive/html/qemu-devel/2016-01/msg02451.html > > > > Basically, what happened with all the previous ideas and proposals? Did a= ny of that work ever get into upstream QEMU? > Is anyone tinkering with the idea of making a paravirtualized Sound Card = and its associated Drivers for the mainstream OSes to try to fix once and f= or all the sound issues?