Re: [RFC PATCH 5/5] mm, page_alloc: Introduce ZONELIST_FALLBACK_SAME_TYPE fallback list

From: Michal Hocko
Date: Thu Apr 25 2019 - 04:09:41 EST


On Thu 25-04-19 07:55:58, Du, Fan wrote:
> >> PMEM is good for frequently read accessed page, e.g. page cache(implicit
> >> page
> >> request), or user space data base (explicit page request)
> >> For now this patch create GFP_SAME_NODE_TYPE for such cases, additional
> >> Implementation will be followed up.
> >
> >Then simply configure that NUMA node as movable and you get these
> >allocations for any movable allocation. I am not really convinced a new
> >gfp flag is really justified.
>
> Case 1: frequently write and/or read accessed page deserved to DRAM

NUMA balancing

> Case 2: frequently read accessed page deserved to PMEM

memory reclaim to move those pages to a more distant node (e.g. a PMEM).

Btw. none of the above is a static thing you would easily know at the
allocation time.

Please spare some time reading surrounding discussions - e.g.
http://lkml.kernel.org/r/1554955019-29472-1-git-send-email-yang.shi@xxxxxxxxxxxxxxxxx
--
Michal Hocko
SUSE Labs