Re: [Qemu-discuss] qemu -cpu host

[Cole Robinson]

You are probably hitting issues with libvirt's 'host-model' behavior:

https://bugzilla.redhat.com/show_bug.cgi?id=870071

Try virt-install --cpu host-passthrough, which maps to qemu's -cpu host, which
is more accurate

- Cole

On 02/06/2017 06:49 AM, akhilesh rawat wrote:
> hi,
> 
> I am using libvirt tool to create instance like below
>  virt-install --virt-type kvm --name compute-0 --cpu host --ram=61440  ....
> 
> And when i check the KVM  process under host this which is doing this Job ..it
> as as below
> 
> usr/libexec/qemu-kvm -name compute-0 -S -machine
> pc-i440fx-rhel7.0.0,accel=kvm,usb=off -cpu
> SandyBridge,+vme,+ds,+acpi,+ss,+ht,+tm,+pbe,+dtes64,+monitor,+ds_cpl,+vmx,+smx,+est,+tm2,+xtpr,+pdcm,+pcid,+dca,+osxsave,+arat,+xsaveopt,+pdpe1gb
> -m 61440
> 
> 
> On Mon, Feb 6, 2017 at 4:59 PM, Narcis Garcia <address@hidden
> <mailto:address@hidden>> wrote:
> 
>     How did you get that translation from "qemu -cpu host" to "...-cpu
>     SandyBridge,+vme,+ds,+acpi,+ss,..." ?
> 
> 
>     El 06/02/17 a les 12:15, akhilesh rawat ha escrit:
>     > thanks , but if you see the guest which was run as
>     >
>     >
>     >     qemu -cpu host
>     >
>     >
>     > has auto generated model as SandyBridge in KVM process.
>     >
>     >  usr/libexec/qemu-kvm -name compute-0 -S -machine
>     > pc-i440fx-rhel7.0.0,accel=kvm,usb=off -cpu
>     > 
> SandyBridge,+vme,+ds,+acpi,+ss,+ht,+tm,+pbe,+dtes64,+monitor,+ds_cpl,+vmx,+smx,+est,+tm2,+xtpr,+pdcm,+pcid,+dca,+osxsave,+arat,+xsaveopt,+pdpe1gb
>     > -m 61440
>     >
>     > So now  running  "--cpu SandyBridge" will make any difference
>     >
>     >
>     >
>     >
>     > On Mon, Feb 6, 2017 at 4:28 PM, Vincenzo Romano
>     > <address@hidden <mailto:address@hidden>
>     <mailto:address@hidden <mailto:address@hidden>>>
>     wrote:
>     >
>     >     2017-02-06 11:36 GMT+01:00 akhilesh rawat
>     >     <address@hidden <mailto:address@hidden>
>     <mailto:address@hidden <mailto:address@hidden>>>:
>     >     >
>     >     > processor    : 19
>     >     > vendor_id    : GenuineIntel
>     >     > cpu family    : 6
>     >     > model        : 42
>     >
>     >     Hmmm. your guest CPU is a different model form the host one.
>     >
>     >     Would you please:
>     >
>     >     - try forcing "SandyBridge" cpu (that'd be your Intel Xeon E312xx)
>     >     instead of host and
>     >     - check the "Recognized CPUID flags" from the output of
>     >     "qemu-system-x86_64 -cpu help" ?
>     >
>     >     --
>     >     Vincenzo Romano - NotOrAnd.IT
>     >     Information Technologies
>     >     --
>     >     NON QVIETIS MARIBVS NAVTA PERITVS
>     >
>     >
> 
>