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Date:   Thu, 25 Apr 2019 10:09:36 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     "Du, Fan" <fan.du@intel.com>
Cc:     "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "Wu, Fengguang" <fengguang.wu@intel.com>,
        "Williams, Dan J" <dan.j.williams@intel.com>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        "xishi.qiuxishi@alibaba-inc.com" <xishi.qiuxishi@alibaba-inc.com>,
        "Huang, Ying" <ying.huang@intel.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH 5/5] mm, page_alloc: Introduce
 ZONELIST_FALLBACK_SAME_TYPE fallback list
Message-ID: <20190425080936.GP12751@dhcp22.suse.cz>
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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@linux.alibaba.com
-- 
Michal Hocko
SUSE Labs