Re: [PATCH] mm/huge_memory: disable thp if thp page size is too large

[David Hildenbrand]

On 06.10.21 10:16, Hao Peng wrote:
> On Thu, Sep 30, 2021 at 9:19 PM David Hildenbrand <david@xxxxxxxxxx> wrote:
> > On 30.09.21 04:14, Hao Peng wrote:
> > > From: Peng Hao <flyingpeng@xxxxxxxxxxx>
> >
> > "disable thp if thp page size is too large" you disable thp if there is
> > not sufficient memory installed in the system (and for that, you use THP
> > size), something doesn't add up here.
> In addition, if THP is enabled, min_free_kbytes will be recalculated.
> At this time,
> min_free_kbytes is calculated based on the size of THP. If the size of
> THP is too l
> arge, OOM will easily be triggered.

Right, I was pointing at the misleading $subject. What about something like:

"mm/huge_memory: disable THP with large THP size on small present memory" ?

> > > After seting the page size to 64k on ARM64, the supported huge page
> >
> > s/seting/setting/
> >
> > Fortunately, most distributions already switched to 4k, because 512MB
> > THP is pretty much useless, especially on any system that doesn't have
> > memory in the range of hundreds of megabytes or terrabytes.
> But the ARM64 Server distribution version I use, such as CentOS for ARM64,
>   has a page size of 16KB or 64KB.

Yeah, RHEL8 and CENTOS8 are the last remaining "recent distirbutions" 
I'm aware of.


--
Thanks,

David / dhildenb