On Thu, Sep 01, 2022 at 09:00:17AM +0200, Peter Zijlstra wrote:

On Wed, Aug 31, 2022 at 11:19:48AM +0100, Mel Gorman wrote:

quoted

It's also unclear *who* would enable this. It looks like it would mostly
have value during the development stage of an embedded platform to track
kernel memory usage on a per-application basis in an environment where it
may be difficult to setup tracing and tracking. Would it ever be enabled
in production? 

Afaict this is developer only; it is all unconditional code.

quoted

Would a distribution ever enable this? 

I would sincerely hope not. Because:

quoted

If it's enabled, any overhead cannot be disabled/enabled at run or
boot time so anyone enabling this would carry the cost without never
necessarily consuming the data.

this.

We could make it a boot parameter, with the alternatives infrastructure - with a
bit of refactoring there'd be a single function call to nop out, and then we
could also drop the elf sections as well, so that when built in but disabled the
overhead would be practically nil.