Question about the *-cpu* option

Question about the *-cpu* option

[LiJun Huang]

Hi.
there is a * -cpu qemu64,+sse2 * in the command line 
http://cleo.tlv.redhat.com/qumrawiki/DanKenigsberg/QemuCli
could any one tell me what's this mean ?
should i set the cpu model as *core2duo* if my host's cpu is *Intel(R) 
Core(TM)2 Duo CPU* ?


Thanks

Re: Question about the *-cpu* option

[Alexander Graf]

On 27.05.2009, at 02:27, LiJun Huang wrote:

> Hi.
> there is a * -cpu qemu64,+sse2 * in the command line http://cleo.tlv.redhat.com/qumrawiki/DanKenigsberg/QemuCli
> could any one tell me what's this mean ?

qemu64 is the "safe" CPU type every modern CPU should support. The  
+sse2 means that additionally SSE2 should be exposed to the guest.  
IIRC SSE2 is part of the qemu64 description already though, so that's  
a rather useless option.

> should i set the cpu model as *core2duo* if my host's cpu is  
> *Intel(R) Core(TM)2 Duo CPU* ?

If you don't need to migrate virtual machines you can use the core2duo  
option to expose a virtual CPU to the guest that's really close to a  
real Core 2 Duo. It's not necessary though and might break under  
certain conditions.

I usually use the qemu64 CPU type on every machine I have, unless I  
run a guest operating system that's picky about the CPU it runs on  
(Mac OS X and Hyper-V mostly).

Alex