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Shutemov" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v5 3/5] mm: LARGE_ANON_FOLIO for improved performance Message-ID: References: <20230810142942.3169679-1-ryan.roberts@arm.com> <20230810142942.3169679-4-ryan.roberts@arm.com> <87v8dg6lfu.fsf@yhuang6-desk2.ccr.corp.intel.com> <5c9ba378-2920-4892-bdf0-174e47d528b7@arm.com> <87cyz43s63.fsf@yhuang6-desk2.ccr.corp.intel.com> <4e14730b-4e4c-de30-04bb-9f3ec4a93754@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4e14730b-4e4c-de30-04bb-9f3ec4a93754@redhat.com> X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: E4B91C0020 X-Stat-Signature: wbaohd8q87i97smkwqihwufiu1wygz8m X-HE-Tag: 1693484982-73423 X-HE-Meta: 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 aLt6l7AL IGMOO7MZHVFbF+w4PYif2bdiElCHJBx5bXWYh2Pfhi/iRdmgKe8M3OusteYw1NQg87j8CT9omMvL0TVyBVFfTa2ZEHHJZ4eRQiSeejKqvT0iT9+5OISgPJGlr7ErC7KTIsDY1kZbMlF7qh+5w9jfTH/iZsPRC/P02SfmQ18ziiO7G0mmc/6qCKknerE2M7KeCV2SxNzR6LNpXDFDjiAhdTsdX5LgZhN9E/2YBe2E8aCtZX7EhMGUgjhD/yj+s/JYsm7pc 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 Thu, Aug 31, 2023 at 09:57:46AM +0200, David Hildenbrand wrote: > As raised in another mail, we can then discuss > * how we want to call this feature (transparent large pages? there is > the concern that "THP" might confuse users. Maybe we can consider > "large" the more generic version and "huge" only PMD-size, TBD) > * how to expose it in stats towards the user (e.g., /proc/meminfo) > * which minimal toggles we want > > I think there *really* has to be a way to disable it for a running system, > otherwise no distro will dare pulling it in, even after we figured out the > other stuff. > > Note that for the pagecache, large folios can be disabled and distributions > are actively making use of that. You can't. Well, you can for shmem/tmpfs, but you have to edit the source code or disable CONFIG_TRANSPARENT_HUGEPAGE to disable it for XFS.