Re: [PATCH v3 0/5] ksm: support tracking KSM-placed zero-pages

[Andrew Morton]

On Tue, 18 Oct 2022 09:00:22 +0000 xu xin <xu.xin.sc@xxxxxxxxx> wrote:

> >A full description of the real-world end-user operational benefits of
> >these changes would help, please.
> >
> 
> The core idea of this patch set is to enable users to perceive the number of any
> pages merged by KSM, regardless of whether use_zero_page switch has been turned
> on, so that users can know how much free memory increase is really due to their
> madvise(MERGEABLE) actions.

OK, thanks.

> The motivation for me to do this is that when I do
> an application optimization of KSM on embedded Linux for 5G platform, I find
> that ksm_merging_pages of some process becomes very small(but used to be large),
> which led me to think that there was any problem with the application KSM-madvise
> strategy, but in fact, it was only because use_zero_pages is on.

Please expand on the above motivation and experience, and include it in
the [0/n] changelog.  But let's leave it a few days to see if there's
additional reviewer input.