Re: [RFC PATCH v0] mm/slub: Let number of online CPUs determine the slub page order

Michal Hocko
2021-01-28T13:58:05Z

On Thu 28-01-21 13:45:12, Mel Gorman wrote:
[...]
> So mostly this is down to the number of times SLUB calls into the page
> allocator which only caches order-0 pages on a per-cpu basis. I do have
> a prototype for a high-order per-cpu allocator but it is very rough --
> high watermarks stop making sense, code is rough, memory needed for the
> pcpu structures quadruples etc.

Thanks this is really useful. But it really begs a question whether this
is a general case or more an exception. And as such maybe we want to
define high throughput caches which would gain a higher order pages to
keep pace with allocation and reduce the churn or deploy some other
techniques to reduce the direct page allocator involvement.
--
Michal Hocko
SUSE Labs