Re: [PATCH v9] pgo: add clang's Profile Guided Optimization infrastructure

Peter Zijlstra
2021-06-14T07:52:14Z

On Sat, Jun 12, 2021 at 01:56:41PM -0700, Bill Wendling wrote:
> For example, Fangrui gave you numbers, and you rejected them out of
> hand. I've explained to you why instrumentation is better than
> sampling (at least for clang). Fangrui gave you numbers. Let's move on
> to something else.

I did not dismiss them; I asked for clarification. I would like to
understand what exactly is missed by sampling based PGO data that makes
such a difference.