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: > > > 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. > > > Would a distribution ever enable this? > > I would sincerely hope not. Because: > > > 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.