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charset=us-ascii Content-Disposition: inline In-Reply-To: <87h6l77wl5.fsf@yhuang6-desk2.ccr.corp.intel.com> X-Rspam-User: X-Stat-Signature: q4r6tgwb8n95ws7wg9kmnynyj9kbpfzf X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: EE99C80004 X-HE-Tag: 1701076253-301377 X-HE-Meta: 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 BhNG6/pB IJqbvI/iaHDMRS1B40fEBLTVvAjnpwy9QbwcXcVb1E8cusyDnJbOnpi37AfZEoXyOkT4iaDs2cQyUFjb7WCoKlRmR9OdLiB6lL2puS0WiSfl5RkpN4rplfyj4/C/D1AbuQ7BhQpzst1NV+WzAdUQSD3pbcshww4QyT4hv5NX9gn7GPhsgwJX7FWHpeF6pOC++skHI9oTybwOPm1y2lsZ7tCszubb7OTRXJScvnkJCE6DSW5qliymMKhaz/b32p/rtCkrdovj5kiurFW3p6Gelxij7sg== 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 Mon 27-11-23 10:34:46, Huang, Ying wrote: > Michal Hocko writes: > > > On Thu 23-11-23 14:15:59, Huang, Ying wrote: > >> Michal Hocko writes: > > [...] > >> > Yes swapcache pages are indeed more complicated but most of the time > >> > they just go away as well, no? > >> > >> When we swapin a page, we will put it in swapcache too. And the page > >> can be in that state for long time if there is more than 50% free space > >> in the swap device. > > > > True, but why is that a problem? If you encounter such a swapped in page > > on the file LRU then the page should be referened and as such should be > > activated, no? > > This just means that anonymous pages in file LRU aren't temporary or > short-term. So we need to consider that. Right. On the other hand we could be more aggressive when dropping the swapcache. Is there any actual reason why we cannot try to folio_free_swap even when mem_cgroup_swap_full == F? -- Michal Hocko SUSE Labs