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Wed, 23 Sep 2026 05:40:20 -0700 (PDT) Date: Wed, 23 Sep 2026 14:40:18 +0200 From: Michal =?utf-8?Q?Koutn=C3=BD?= To: Andrew Morton Cc: Qinyun Tan , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , David Hildenbrand , Zi Yan , Baolin Wang , Usama Arif , Dave Chinner , Qi Zheng , Yosry Ahmed , Nhat Pham , Chengming Zhou , Xunlei Pang , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/4] mm: restore per-memcg reclaim for NONSLAB shrinkers under nokmem Message-ID: References: <20260910080722.3961351-1-qinyuntan@linux.alibaba.com> <20260922183547.788d21b89868bf820e94cc62@linux-foundation.org> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="jduqwrsbz2lze7tg" Content-Disposition: inline In-Reply-To: <20260922183547.788d21b89868bf820e94cc62@linux-foundation.org> --jduqwrsbz2lze7tg Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v3 0/4] mm: restore per-memcg reclaim for NONSLAB shrinkers under nokmem MIME-Version: 1.0 On Tue, Sep 22, 2026 at 06:35:47PM -0700, Andrew Morton wrote: > On Thu, 10 Sep 2026 16:07:18 +0800 Qinyun Tan wrote: >=20 > > With cgroup.memory=3Dnokmem, the THP deferred split shrinker and the > > zswap shrinker are degraded in two ways. >=20 > Obvious question which may have recently been addressed: >=20 > Why are we keeping nokmem around? How useful are its memory savings > and is anyone actually using it? Besides (not so significant) memory savings, there are also runtime savings (not spending time with accounting of each kernel allocation) and environmnents where shared (not)accounting of kernel objects is preferred (as other resources than memory are shared anyways). The above are IMO justifiable reasons and I know such users. HTH, Michal --jduqwrsbz2lze7tg Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iJEEABYKADkWIQRCE24Fn/AcRjnLivR+PQLnlNv4CAUCarPImhsUgAAAAAAEAA5t YW51MiwyLjUrMS4xMiwyLDIACgkQfj0C55Tb+AhuYwEAq+e3Y6FWb+6/NZTcNcD/ OwbFXuc9bSQF8eyv2blq63IA/3OX78kjmj6FDtiaJ3JiP6ozQ4i+Uppjk/m6YUto JN8K =dA2e -----END PGP SIGNATURE----- --jduqwrsbz2lze7tg--