Re: [PATCHv5] mm: optimization on page allocation when CMA enabled

[Andrew Morton]

On Sun, 8 Oct 2023 15:54:40 +0800 Zhaoyang Huang <huangzhaoyang@xxxxxxxxx> wrote:

> > Roman previously asked
> >
> > : Also I'm a bit concerned about potential performance implications.
> > : Would be great to provide some benchmarks or some data.  Probably it's
> > : ok because of we have pcp caches on top, but I'm not 100% sure.
> >
> > Are you able to perform such testing and tell us the result?
> I have applied this patch in a v5.4 based ANDROID system and got no
> regression problem. Actually, this commit is aimed to have
> alloc_pages(GFP_USER) use CMA instead of stealing U&R(could lead to
> GFP_KERNEL fail) only when zone's free pages and free cma are around
> WATERMARK_LOW/MIN which would NOT affect most scenarios.

OK, thanks.

Could the appropriate people please take a look at this?  It has been
in mm-unstable since May.

Thanks.