Re: [PATCH RFC 8/9] KVM: Add dirty-ring-size property

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Peter Xu (peterx@redhat.com) wrote:
> Add a parameter for size of dirty ring.  If zero, dirty ring is
> disabled.  Otherwise dirty ring will be enabled with the per-vcpu size
> as specified.  If dirty ring cannot be enabled due to unsupported
> kernel, it'll fallback to dirty logging.  By default, dirty ring is
> not enabled (dirty-ring-size==0).
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---

<snip>

> diff --git a/qemu-options.hx b/qemu-options.hx
> index 224a8e8712..140bd38726 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -119,6 +119,7 @@ DEF("accel", HAS_ARG, QEMU_OPTION_accel,
>      "                kernel-irqchip=on|off|split controls accelerated irqchip support (default=on)\n"
>      "                kvm-shadow-mem=size of KVM shadow MMU in bytes\n"
>      "                tb-size=n (TCG translation block cache size)\n"
> +    "                dirty-ring-size=n (KVM dirty ring size in Bytes)\n"
>      "                thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL)
>  STEXI
>  @item -accel @var{name}[,prop=@var{value}[,...]]
> @@ -140,6 +141,8 @@ irqchip completely is not recommended except for debugging purposes.
>  Defines the size of the KVM shadow MMU.
>  @item tb-size=@var{n}
>  Controls the size (in MiB) of the TCG translation block cache.
> +@item dirty-ring-size=@val{n}
> +Controls the size (in Bytes) of KVM dirty ring (<=0 to disable).

I think that needs to say 'per vcpu'

Dave

>  @item thread=single|multi
>  Controls number of TCG threads. When the TCG is multi-threaded there will be one
>  thread per vCPU therefor taking advantage of additional host cores. The default
> -- 
> 2.24.1
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK