Re: [PATCH v5 1/2] xenbus/backend: Add memory pressure handler callback

[JÃrgen GroÃ]

On 10.12.19 09:06, SeongJae Park wrote:
> Granting pages consumes backend system memory.  In systems configured
> with insufficient spare memory for those pages, it can cause a memory
> pressure situation.  However, finding the optimal amount of the spare
> memory is challenging for large systems having dynamic resource
> utilization patterns.  Also, such a static configuration might lack a
> flexibility.
>
> To mitigate such problems, this commit adds a memory reclaim callback to
> 'xenbus_driver'.  Using this facility, 'xenbus' would be able to monitor
> a memory pressure and request specific devices of specific backend
> drivers which causing the given pressure to voluntarily release its
> memory.
>
> That said, this commit simply requests every callback registered driver
> to release its memory for every domain, rather than issueing the
> requests to the drivers and the domain in charge.  Such things will be
> done in a futur.  Also, this commit focuses on memory only.  However, it
> would be ablt to be extended for general resources.
>
> Signed-off-by: SeongJae Park <sjpark@xxxxxxxxx>

Reviewed-by: Juergen Gross <jgross@xxxxxxxx>


Juergen