|
From: | Hao Luo |
Subject: | Re: [Qemu-devel] [PATCH 6/6] usb-tablet: Allow connecting to ehci |
Date: | Wed, 26 Dec 2012 23:53:29 +0800 |
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"<address@hidden>
抄送:"Hans de
Goede"<address@hidden>,"qemu-devel"<address@hidden>
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 <address@hidden>
>
> 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 <address@hidden>
> Signed-off-by: Gerd Hoffmann <address@hidden>
>
> tablet compat fixup
>
> Signed-off-by: Gerd Hoffmann <address@hidden>
|
[Prev in Thread] | Current Thread | [Next in Thread] |