qemu-1.2 and later (so F-18+) have a regression where the audio_timer tries to expires every nano second, which gets rate limited to every 250 us by the timer subsys, resulting in 4000 wakeups per seconds for vms with audio active. Here is an upstream patch fixing this: http://lists.nongnu.org/archive/html/qemu-devel/2013-10/msg01204.html Dropping host cpu load to a much better 13%. And here is a follow up patch further limiting the wakeup rate from 250 / second (which is a bit much) to 100 / second: http://lists.nongnu.org/archive/html/qemu-devel/2013-10/msg01205.html Further reducing the host cpu load for playing audio to 9%. Note master had some timer functions renamed, so the 1st patch won't apply as is, backporting it is trivial though.
Since only the first patch is upstream right now and seems the most important one, I'll just pull that.
qemu-1.6.1-1.fc20 has been submitted as an update for Fedora 20. https://admin.fedoraproject.org/updates/qemu-1.6.1-1.fc20
(In reply to Cole Robinson from comment #1) > Since only the first patch is upstream right now and seems the most > important one, I'll just pull that. ACK.
Package qemu-1.6.1-1.fc20: * should fix your issue, * was pushed to the Fedora 20 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing qemu-1.6.1-1.fc20' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2013-20776/qemu-1.6.1-1.fc20 then log in and leave karma (feedback).
qemu-1.6.1-1.fc20 has been pushed to the Fedora 20 stable repository. If problems still persist, please make note of it in this bug report.