[libvirt][PATCH v4 0/3] introduce 'restrictive' mode in numatune

[Daniel P. Berrangé]

On Tue, Mar 23, 2021 at 10:59:02AM +0800, Luyao Zhong wrote:
> Before this patch set, numatune only has three memory modes:
> static, interleave and prefered. These memory policies are
> ultimately set by mbind() system call.
> 
> Memory policy could be 'hard coded' into the kernel, but none of
> above policies fit our requirment under this case. mbind() support
> default memory policy, but it requires a NULL nodemask. So obviously
> setting allowed memory nodes is cgroups' mission under this case.
> So we introduce a new option for mode in numatune named 'restrictive'.
> 
> <numatune>
>    <memory mode="restrictive" nodeset="1-4,^3"/>
>    <memnode cellid="0" mode="restrictive" nodeset="1"/>
>    <memnode cellid="2" mode="restrictive" nodeset="2"/>
> </numatune>

'restrictive' is rather a wierd name and doesn't really tell me what
the memory policy is going to be. As far as I can tell from the
patches, it seems this causes us to not set any memory alllocation
policy at all. IOW, we're using some undefined host default policy.

Given this I think we should be calling it either "none" or "default"


Regards,
Daniel
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