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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: E948C40007 X-Stat-Signature: r1ksdqqk38wi591s488mzuoey381f1s5 X-HE-Tag: 1700459534-111815 X-HE-Meta: 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 glGxpri0 GBO3ABmqFNyJvvJKQ/bjWUaqXm4dnYR5k55pH9dEG0/NW+4vNeYrhcSa4ib4VzEvRmngb5Y56Xqe5lN0Z7GZmx6kTwyrk/P0sNYtVZytM4EbPE7Jb2GN8BfknIdz/I3F3Fz48V18A2CSrrKK2xnmzseyIt3W1vyB1P+2mkgb3dHcO+YYOBQKhZ2ES94Wkx/aHW7tpmLMktFGustQDdfkt6YSm+wweFPBKFcXrMlI/2E0TgUJcQpdDsKpw3PIH6Iu+8f8U5cCzV/XBprGLZDr27VgbbRYss/GsBuUMqTkHP+Dgulc= 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: List-Subscribe: List-Unsubscribe: On Sun, Nov 19, 2023 at 9:41=E2=80=AFPM Huang, Ying = wrote: > > Chris Li writes: > > > On Sun, Nov 19, 2023 at 7:20=E2=80=AFPM Huang, Ying wrote: > > Per my understanding, memcg uncharging happens in > > swapcache_free_entries() > swap_entry_free() > mem_cgroup_uncharge_swap() > > The swap entries are uncharged one-by-one, not Yes. That matches my understanding as well. I think I am using the term "batching" very loosely. My bad and thanks for the clarification. I am referring to the fact that in most cases, the free_swap_slot() does not perform uncharge. It is grouped together with other entries to uncharge together inside swapcache_free_entries(). Yes, the uncharge itself is done by a for loop page by page. No batching in the for loop. BTW, Not all uncharges can be batched, because they can come from different memcg. Chris