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[2003:cb:c749:6900:3a06:bd5:2f7b:e6eb]) by smtp.gmail.com with ESMTPSA id m4-20020adff384000000b00321673de0d7sm1385747wro.25.2023.09.27.02.57.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 27 Sep 2023 02:57:34 -0700 (PDT) Message-ID: Date: Wed, 27 Sep 2023 11:57:34 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCH v3 1/4] mm/ksm: add "smart" page scanning mode To: Stefan Roesch , Andrew Morton Cc: kernel-team@fb.com, hannes@cmpxchg.org, riel@surriel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20230926040939.516161-1-shr@devkernel.io> <20230926040939.516161-2-shr@devkernel.io> <20230926140955.8b2627711116339af80731f2@linux-foundation.org> Content-Language: en-US From: David Hildenbrand Organization: Red Hat In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27.09.23 02:39, Stefan Roesch wrote: > > 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 > +1 Reviewed-by: David Hildenbrand -- Cheers, David / dhildenb