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Tue, 26 Sep 2023 20:39:27 -0400 (EDT) References: <20230926040939.516161-1-shr@devkernel.io> <20230926040939.516161-2-shr@devkernel.io> <20230926140955.8b2627711116339af80731f2@linux-foundation.org> User-agent: mu4e 1.10.1; emacs 28.2.50 From: Stefan Roesch To: Andrew Morton Cc: David Hildenbrand , kernel-team@fb.com, hannes@cmpxchg.org, riel@surriel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v3 1/4] mm/ksm: add "smart" page scanning mode Date: Tue, 26 Sep 2023 17:39:09 -0700 In-reply-to: <20230926140955.8b2627711116339af80731f2@linux-foundation.org> Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Spam-Status: No, score=-0.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on pete.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (pete.vger.email [0.0.0.0]); Tue, 26 Sep 2023 20:08:48 -0700 (PDT) Andrew Morton writes: > On Tue, 26 Sep 2023 09:13:31 -0700 Stefan Roesch wrote: > >> > Thinking about it, what are the cons of just enabling this always and not >> > exposing new toggles? Alternatively, we could make this a compile-time option. >> > >> > In general, LGTM, just curious if we really have to make this configurable. >> > >> >> The only downside I can see is that it might take a longer time for some >> pages to be de-duplicated (a new candidate page is added, but its >> duplicate is skipped in this round). So it will take longer to >> de-duplicate this page. >> >> I tested with more than one workload, but it might be useful to get some >> data with additional workloads. I was thinking of enabling it after one or >> two releases. > > We could keep the tunable and make it default "on"? Sounds good to me