[pve-devel] qemu 1.4 and usb-tablet

[Alexandre DERUMIER]

>>Any idea who we can use that? 

Simply connect the usb-tablet to ehci controller ?

Maybe is it time to use ehci by default ? (It's migratable now).
And seem that is use lower cpu (maybe less interrupts ?)

the qemu git commit is here :

http://git.qemu.org/?p=qemu.git;a=commit;h=427e3aa151c749225364d0c30640e2e3c1756d9d

"
usb-tablet: Allow connecting to ehci



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."


----- Mail original ----- 

De: "Dietmar Maurer" <dietmar at proxmox.com> 
À: pve-devel at pve.proxmox.com 
Envoyé: Dimanche 17 Février 2013 15:44:01 
Objet: [pve-devel] qemu 1.4 and usb-tablet 

I already updated our git to include the new qemu 1.4 code. 

>From the changelog: 
> * usb: usb-tablet can be connected as an USB 2.0 device, lowering the CPU 
> usage substantially 

Any idea who we can use that? 


_______________________________________________ 
pve-devel mailing list 
pve-devel at pve.proxmox.com 
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel