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charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Mar 20, 2023 at 03:06:47AM +0000, Cai Xinchen wrote: > There are two problems left: >=20 > root > / \ > A B > / \ \ > C E D >=20 > 1. In some case of reparent, some page cache may be used by other memcg > D but it charges to the parent memcg A of dying memcg E. D is getting > away with using the page for free while A is taxed. Note that A is (effectively) taxed even before E is removed due to hierarchical nature of charging. Then what you describe transforms into "well-known" problem of shared charging (with not well-known solution :-/). HTH, Michal --7ps5la3sopyo7hm5 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTrXXag4J0QvXXBmkMkDQmsBEOquQUCZB3aYQAKCRAkDQmsBEOq uULUAQCHRvKpQPSDHUkOEFl2uZo3E7GeJT8AUOQoAsdb9Scv3wEA6jAYPC9q+nvp FbwIeniHgYs6j4F0z5/Y/u/CsVBLuQw= =CvmU -----END PGP SIGNATURE----- --7ps5la3sopyo7hm5--