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[71.184.117.43]) by smtp.gmail.com with ESMTPSA id d23sm13393985qkc.127.2019.10.24.04.11.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 24 Oct 2019 04:11:53 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH] mm/vmstat: Reduce zone lock hold time when reading /proc/pagetypeinfo Date: Thu, 24 Oct 2019 07:11:52 -0400 Message-Id: References: <20191024074205.GQ17610@dhcp22.suse.cz> Cc: Andrew Morton , Waiman Long , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Johannes Weiner , Roman Gushchin , Vlastimil Babka , Konstantin Khlebnikov , Jann Horn , Song Liu , Greg Kroah-Hartman , Rafael Aquini In-Reply-To: <20191024074205.GQ17610@dhcp22.suse.cz> To: Michal Hocko X-Mailer: iPhone Mail (17A878) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > On Oct 24, 2019, at 3:42 AM, Michal Hocko wrote: >=20 > It's been useful for debugging memory fragmentation problems and we do > not have anything that would provide a similar information. Considering Actually, zoneinfo and buddyinfo are somewhat similar to it. Why the extra i= nformation in pagetypeinfo is still useful in debugging today=E2=80=99s real= -world scenarios? > that making it root only is trivial and reducing the lock hold times > likewise I do not really see any strong reason to dump it at this > moment. There is no need to hurry this, and clearly this is rather a good opportunit= y to discuss the consolidation of memory fragmentation debugging to ease the= maintenance in long term.=