Re: [pve-devel] [PATCH-SERIES qemu/qemu-server/manager 0/1] add and set x86-64-v2 as default model for new vms

["Fabian Grünbichler" <f.gruenbichler@proxmox.com>]

On May 17, 2023 9:02 am, Alexandre Derumier wrote:
> Hi,
> 
> we used kvm64 as default cpumodel since the begin of proxmox. (basically, it's like a pentium4 cpu flags).
> 
> New distros like rhel9 are compiled to use more modern cpu flags.
> (and windows already use new flags since year, and we already add some extra cpu flags)
> 
> "
> In 2020, AMD, Intel, Red Hat, and SUSE worked together to define
> three microarchitecture levels on top of the historical x86-64
> baseline:
> 
>   * x86-64:    original x86_64 baseline instruction set
>   * x86-64-v2: vector instructions up to Streaming SIMD
>                Extensions 4.2 (SSE4.2)  and Supplemental
>                Streaming SIMD Extensions 3 (SSSE3), the
>                POPCNT instruction, and CMPXCHG16B
>   * x86-64-v3: vector instructions up to AVX2, MOVBE,
>                and additional bit-manipulation instructions.
>   * x86-64-v4: vector instructions from some of the
>                AVX-512 variants.
> 
> "
> 
> 
> (x86-64 is kvm64/qemu64 cpu model).
> 
> This patch series add new models (patch was found on qemu mailing, but never appplied).
> 
> "x86-64-abiX" : (as vX are reserved in qemu for revision versioning)
> 
> https://lore.kernel.org/all/20210526144038.278899-1-berrange@redhat.com/T/

FWIW, there was a v3: https://lists.gnu.org/archive/html/qemu-devel/2021-06/msg01591.html
(20210607135843.196595-1-berrange@redhat.com) that has some more
discussion/information (only the doc table + script to generate it have
been applied it seems).