Re: slow boot with 7fef431be9c9 ("mm/page_alloc: place pages to tail in __free_pages_core()")

[Mike Rapoport]

Hi,

On Sat, Mar 13, 2021 at 10:05:23AM +0100, David Hildenbrand wrote:
> > Am 13.03.2021 um 05:04 schrieb Liang, Liang (Leo) <Liang.Liang@xxxxxxx>:
> > 
> > Hi David,
> > 
> > Which benchmark tool you prefer? Memtest86+ or else?
> 
> Hi Leo,
> 
> I think you want something that runs under Linux natively.
> 
> I‘m planning on coding up a kernel module to walk all 4MB pages in the
> freelists and perform a stream benchmark individually. Then we might be
> able to identify the problematic range - if there is a problematic range :)

My wild guess would be that the pages that are now at the head of free
lists have wrong caching enabled. Might be worth checking in your test
module.

> Guess I‘ll have it running by Monday and let you know.
> 
> Cheers!

-- 
Sincerely yours,
Mike.