Re: [XEN RFC PATCH 00/40] Add device tree based NUMA support to Arm64

[Julien Grall <julien@xxxxxxx>]

On 19/08/2021 15:05, Bertrand Marquis wrote:
> Hi Julien,
Hi Bertrand,

> > On 19 Aug 2021, at 14:42, Julien Grall <julien@xxxxxxx> wrote:
> >
> > Hi Wei,
> >
> > On 11/08/2021 11:23, Wei Chen wrote:
> > > Xen memory allocation and scheduler modules are NUMA aware.
> > > But actually, on x86 has implemented the architecture APIs
> > > to support NUMA. Arm was providing a set of fake architecture
> > > APIs to make it compatible with NUMA awared memory allocation
> > > and scheduler.
> > > Arm system was working well as a single node NUMA system with
> > > these fake APIs, because we didn't have multiple nodes NUMA
> > > system on Arm. But in recent years, more and more Arm devices
> > > support multiple nodes NUMA system. Like TX2, some Hisilicon
> > > chips and the Ampere Altra.
> > All the platforms you mention here are servers (so mainly ACPI). However, this 
> > series is adding DT support.
> >
> > Could you outline the long term plan for DT? Is it going to be used on 
> > production HW?
> Yes we are already and will continue to use this on production HW.
> Some embedded hardware will have some usage of NUMA (as some embedded functions 
> do require lots of computing power).
Interesting! Thank you for the clarifications.

> We are doing experiments of that right now using those patches.
Cheers,

--
Julien Grall