Re: [Qemu-devel] Questions about hvm domU default devices with upstream qemu

[Fabio Fantoni]

Il 04/07/2013 15:51, Fabio Fantoni ha scritto:
> Last year I posted a question about default devices of upstream qemu 
> that differ from qemu traditional, like empty floppy and cdrom in 
> particular.
> About empty floppy now is disabled as workaround.
> About empty cdrom Stabellini tells that is useful, so I tried to use 
> it but cd-insert was failing,and I must define other empty cdrom on xl 
> configuration file, for example with: ',raw,hdb,ro,cdrom'.
> It seem that there isn't default devices usable without define them in 
> xen, and I think that probably need to revise the definition of the 
> devices to avoid empty and unusable ones and to do everything as best 
> as possible (also with possibly reviewing qemu side).
> Another good thing is also consider pv domU case and possible future 
> support of spice and/or other useful features.
> Thanks for any reply.

I seen no replies about this, I think is important improve upstream qemu 
support and remove the traditional ASA upstream will be equivalent or 
superior in all features.

I also think is good idea add q35 support on xen.
Seem that hvm domUs have performance limits, in particular on windows 
domUs (also with pv drivers) caused probably by old hardware emulation 
by qemu and/or xen support limited on some instruction sets.
I don't know how to add essential q35 support on hvmloader to do some 
tests and have effective data about improvements.
Anyone on this?

Thanks for any reply.