Re: [RFC] Adding support for setting the affinity of the recording process

[Yang Jihong]

Hello,

On 2023/6/12 23:05, Peter Zijlstra wrote:
> On Mon, Jun 12, 2023 at 11:24:26AM -0300, Arnaldo Carvalho de Melo wrote:
> > But could you please spell out the use case, why do you need this, is
> > this so common (for you) that you repeatedly need to first taskset, then
> > perf, etc?
>
> I'm thinking this is due to big.LITTLE things where the PMUs on the CPUs
> are different. Intel recently having stepped into this trainwreck,
> there's now a ton more people 'enjoying' it ...
>
> So what people often do it is affine the process to one type of CPU and
> then perf it so that their measurements are consistent.
Yes, it's a scene, the purpose of setting affinity is to ensure the 
stability of recorded events.

> It all sucks, but given the situation, it might be the best option :/
>
> Ian was working on improving the whole hybrid thing, perhaps he has more
> opinions.
Thank you for your reply.

> .

Thanks,
Yang.