Date: Fri, 8 Dec 2017 09:47:55 +0100
From: Michal Hocko <mhocko@kernel.org>
To: kemi <kemi.wang@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Mel Gorman <mgorman@techsingularity.net>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Christopher Lameter <cl@linux.com>,
        YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Nikolay Borisov <nborisov@suse.com>,
        Pavel Tatashin <pasha.tatashin@oracle.com>,
        David Rientjes <rientjes@google.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Dave <dave.hansen@linux.intel.com>, Andi Kleen <andi.kleen@intel.com>,
        Tim Chen <tim.c.chen@intel.com>,
        Jesper Dangaard Brouer <brouer@redhat.com>,
        Ying Huang <ying.huang@intel.com>, Aaron Lu <aaron.lu@intel.com>,
        Aubrey Li <aubrey.li@intel.com>, Linux MM <linux-mm@kvack.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] mm: NUMA stats code cleanup and enhancement
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On Fri 08-12-17 16:38:46, kemi wrote:
> 
> 
> On 2017年11月30日 17:45, Michal Hocko wrote:
> > On Thu 30-11-17 17:32:08, kemi wrote:
> 
> > Do not get me wrong. If we want to make per-node stats more optimal,
> > then by all means let's do that. But having 3 sets of counters is just
> > way to much.
> > 
> 
> Hi, Michal
>   Apologize to respond later in this email thread.
> 
> After thinking about how to optimize our per-node stats more gracefully, 
> we may add u64 vm_numa_stat_diff[] in struct per_cpu_nodestat, thus,
> we can keep everything in per cpu counter and sum them up when read /proc
> or /sys for numa stats. 
> What's your idea for that? thanks

I would like to see a strong argument why we cannot make it a _standard_
node counter.
-- 
Michal Hocko
SUSE Labs