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Date: Mon, 5 Feb 2018 13:30:13 +0800
From: Aaron Lu <aaron.lu@intel.com>
To: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Huang Ying <ying.huang@intel.com>, Dave Hansen <dave.hansen@intel.com>,
        Kemi Wang <kemi.wang@intel.com>, Tim Chen <tim.c.chen@linux.intel.com>,
        Andi Kleen <ak@linux.intel.com>, Michal Hocko <mhocko@suse.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Mel Gorman <mgorman@techsingularity.net>,
        Daniel Jordan <daniel.m.jordan@oracle.com>
Subject: RFC: eliminate zone->lock contention for will-it-scale/page_fault1
 on big server
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In addition the the two patches, there are two more patches that I would
like to get some feedback.

The two patches are more radical: the 3rd deals with free path
zone->lock contention by avoiding doing any merge for order0 pages while
the 4th deals with allocation path zone->lock contention by taking
pcp->batch pages off the free_area order0 list without the need to
iterate the list.

Both patches are developed based on "the most time consuming part of
operations under zone->lock is cache misses on struct page".

The 3rd patch may be controversial but doesn't have correctness problem;
the 4th is in an early stage and serves only as a proof-of-concept.

Your comments are appreciated, thanks.