Re: [RESEND PATCH v7 00/10] Small-sized THP for anonymous memory

From: Matthew Wilcox
Date: Thu Nov 23 2023 - 11:18:39 EST


On Thu, Nov 23, 2023 at 05:05:37PM +0100, David Hildenbrand wrote:
> On 23.11.23 16:59, Matthew Wilcox wrote:
> > On Wed, Nov 22, 2023 at 04:29:40PM +0000, Ryan Roberts wrote:
> > > Note: I'm resending this at Andrew's suggestion due to having originally sent
> > > it during LPC. I'm hoping its in a position where the feedback is minor enough
> > > that I can rework in time for v6.8, but so far haven't had any.
> > >
> > > Hi All,
> > >
> > > This is v7 of a series to implement small-sized THP for anonymous memory
> > > (previously called "large anonymous folios"). The objective of this is to
> >
> > I'm still against small-sized THP. We've now got people asking whether
> > the THP counters should be updated when dealing with large folios that
> > are smaller than PMD sized. It's sowing confusion, and we should go
> > back to large anon folios as a name.
> >
>
> I disagree.
>
> https://lore.kernel.org/all/65dbdf2a-9281-a3c3-b7e3-a79c5b60b357@xxxxxxxxxx/

And yet:
https://lore.kernel.org/linux-mm/20231106193315.GB3661273@xxxxxxxxxxx/

"This is a small THP so we don't account it as a THP, we only account
normal THPs as THPs" is a bizarre position to take.

Not to mention that saying a foo is a small huge baz is just bizarre.
Am I a small giant? Or just a large human?