qemu Enables support for Linux's Async IO Enable alsa output for sound emulation Adds support for braille displays using brltty Support ISOs / -cdrom directives vis HTTP or HTTPS. Enables firmware device tree support Enable audio mixer emulation. On Fedora, known to cause performance problems when using SDL output and ALSA. For OSS, locks the sound device from other applications. Enable the ncurses-based console Enable pulseaudio output for sound emulation Provides the qemu-ifup script for use with QEMU's built in bridging Enable rados block device backend support, see http://ceph.newdream.net/wiki/QEMU-RBD Enable the SDL-based console Enable Spice protocol support via app-emulation/spice Enable SystemTAP/DTrace tracing Enable the TCG Interpreter which can speed up or slowdown workloads depending on the host and guest CPUs being emulated. In the future it will be a runtime option but for now its compile time. Enable TLS support for the VNC console server Use sys-apps/usbredir to redirect USB devices to another machine over TCP Enable VDE-based networking Enable accelerated networking using vhost-net, see http://www.linux-kvm.org/page/VhostNet Enable VirtFS support. See http://wiki.qemu.org/Documentation/9psetup Add support for getting and setting POSIX extended attributes, through sys-apps/attr. Requisite for the virtfs backend. Enables support for Xen backends Support xfsctl() notification and syncing for XFS backed virtual disks.