Erik, You can take a look at my recent post about usb tablet peforamnce over ehci, in which I mentioned a libvirt config of how to let usb tablet connect to ehci.
2012-12-26 Hao Luo 发件人：Erik Rull 发送时间：2012-12-26 20:08 主题：Re: [Qemu-devel] [PATCH 6/6] usb-tablet: Allow connecting to ehci 收件人："Gerd Hoffmann"<kra...@redhat.com> 抄送："Hans de Goede"<hdego...@redhat.com>,"qemu-devel"<qemu-devel@nongnu.org> Hi Gerd, hi Hans, is my assumption correct that if I check out and compile this version from GIT master that the usb-tablet device is automatically routed to ehci without changing anything else in the qemu call arguments? (And the performance enhancement takes place automatically) If not - what has to be changed to get it working? Best regards, Erik Gerd Hoffmann wrote: > From: Hans de Goede <hdego...@redhat.com> > > Our ehci code has is capable of significantly lowering the wakeup rate > for the hcd emulation while the device is idle. It is possible to add > similar code ot the uhci emulation, but that simply is not there atm, > and there is no reason why a (virtual) usb-tablet can not be a USB-2 device. > > Making usb-hid devices connect to the emulated ehci controller instead > of the emulated uhci controller on vms which have both lowers the cpuload > for a fully idle vm from 20% to 2-3% (on my laptop). > > An alternative implementation to using a property to select the tablet > type, would be simply making it a new device type, ie usb-tablet2, but the > downside of that is that this will require libvirt changes to be available > through libvirt at all, and then management tools changes to become the > default for new vms, where as using a property will automatically get > any pc-1.3 type vms the lower cpuload. > > [ kraxel: adapt compat property for post-1.3 merge ] > > Signed-off-by: Hans de Goede <hdego...@redhat.com> > Signed-off-by: Gerd Hoffmann <kra...@redhat.com> > > tablet compat fixup > > Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
