RE: [PATCH] config/x86: config support for AMD EPYC processors

["Tummala, Sivaprasad" <Sivaprasad.Tummala@amd.com>]

[AMD Official Use Only - General]

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Friday, October 6, 2023 1:21 PM
> To: Tummala, Sivaprasad <Sivaprasad.Tummala@amd.com>
> Cc: bruce.richardson@intel.com; konstantin.v.ananyev@yandex.ru; dev@dpdk.org;
> dpdk-techboard <techboard@dpdk.org>; Thomas Monjalon
> <thomas@monjalon.net>
> Subject: Re: [PATCH] config/x86: config support for AMD EPYC processors
>
> Caution: This message originated from an External Source. Use proper caution
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>
>
> On Mon, Sep 25, 2023 at 5:11 PM Sivaprasad Tummala
> <sivaprasad.tummala@amd.com> wrote:
> >
> > From: Sivaprasad Tummala <Sivaprasad.Tummala@amd.com>
> >
> > By default, max lcores are limited to 128 for x86 platforms.
> > On AMD EPYC processors, this limit needs to be increased to leverage
> > all the cores.
> >
> > The patch adjusts the limit specifically for native compilation on AMD
> > EPYC CPUs.
> >
> > Signed-off-by: Sivaprasad Tummala <Sivaprasad.Tummala@amd.com>
>
> This patch is a revamp of
> http://inbox.dpdk.org/dev/BY5PR12MB3681C3FC6676BC03F0B42CCC96789@BY5PR
> 12MB3681.namprd12.prod.outlook.com/
> for which a discussion at techboard is supposed to have taken place.
> But I didn't find a trace of it.
>
> One option that had been discussed in the previous thread was to increase the
> max number of cores for x86.
> I am unclear if this option has been properly evaluated/debatted.
>
> Can the topic be brought again at techboard?

Hi David,

The patch is intended to detect AMD platforms and enable all CPU cores by
default on native builds.

As an optimization for memory footprint, users can override this by specifying
"-Dmax_lcores" option based on DPDK lcores required for their usecases.

Sure, will request to add this topic for discussion at techboard.
>
> Thanks.
>
> --
> David Marchand