From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793165733; b=Zzge49+cZPR3r9X+Dn4NvkyaeKM2u1sbbN8JhadvrZN2nTZ074N4J04LJV2BKda+bb7Y jXNHT8ulU1wwevbhxZvCysTcFdQf9RS4FgsDUa0yXCAXhoF0W33t0DuxnUIOfeMepDaza T9f2k3Q+8M3g+2HknrV7Ouw2z6gE5f8icXaxTLarNtjR1sdSk5gFoJduCAgtK2SVtFlc6 EZ5RdwKAT5yGLErZcWTsgA472hyZI+OYUbby+1WnPayc9gePWuD2HQaBIAWANvyksM0ww LhiJ78g//Vfgry+8fuBynzCBT4mbozAQVL/Na2A2wNDDS5eFNquPXUX0Df8Unoc6Sew== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793165733; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=oCF8kfzyKgaGcmmngoeyp1DL7LEberyF6cj2vg7mrCw=; b=2zsOysCGaCsIDlOCO1JHIARYfD2ZRYQ8Qs8kPLRbhF7Hlwho4kWBMqk9f7Xt4r2rjJA1 kYhnvqvf20eYJKiBPsrp8E8v8Qj663sdAbFocmkSJzGy2SF7CBqEVa2TX8TBMLWtmbSlz lvyBim89w/Za8mwLtWzzizXUJeIgKDDBCEAfJZjxw+8NlguQ/im6YSNi4hJOTldAY6Pgi xUD4FqCU53lwUlW41mcuoaNCDNPtFTByfb+uElPsRCQzCuI0nI24OwAso1IZXQYLp5kR0 BXJjdgnzSkPaLuiWcgeO7dUDXZ32v5BnCAt0q4zXF9NXxynJ79NbW7fuo4XUuoAME6g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Vx5RaM+k; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 532C6606A31A; Wed, 28 Oct 2026 05:35:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Vx5RaM+k Received: by smtp.kernel.org (Postfix) with ESMTPSA id A18281F01825; Wed, 28 Oct 2026 05:35:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793165732; bh=oCF8kfzyKgaGcmmngoeyp1DL7LEberyF6cj2vg7mrCw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Vx5RaM+kkDCqcYpK1TthH4mUUylEW9pvnlM6hLj9wD4ydPVPP79FDITUhr9XcbipY 9xGaEUTpZYpgQ9miH23CU1NgqEyRkQZb80TARyylyHKAOdJOhpuqm5yprWDKtFy75b 6xxyldCvVpHTDB9UygE0jMu+x5UF1FdfqeD5d9AWFbVW2cTOl4/rclO+W6+FpvoD89 ZoAYLpIJB7rZCZdEUcZzYeGBiSbybOQw6wLxYFa6Oy06VxwoqEq6j+ulym67/NwrLm w65uM6fn6G3cPMnY/02Yk6Ij8crJhSIV78SBss9kcKuM4ZJ57rBWCVjPbBIfRisemq D3Sf+ymu+jUsw== From: SJ Park To: SJ Park Cc: Jinjie Ruan , corbet@lwn.net, skhan@linuxfoundation.org, rdunlap@infradead.org, damon@lists.linux.dev, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Docs/admin-guide/mm/damon/reclaim: document how to disable watermarks Date: Tue, 27 Oct 2026 22:35:25 -0700 Message-ID: <20261028053525.155909-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261028052425.154616-1-sj@kernel.org> References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Tue, 27 Oct 2026 22:24:24 -0700 SJ Park wrote: > Hello Jinjie, > > On Wed, 28 Oct 2026 10:36:28 +0800 Jinjie Ruan wrote: > > > DAMON_RECLAIM runs its scheme only while the free memory rate is > > between `wmarks_low` and `wmarks_mid`. > > > > But some users want to reclaim cold pages even while the system has > > plenty of free memory, and it is not obvious that the existing > > watermarks parameters can already do that. So Document the setup. > > Thank you for this patch! > > > > > Signed-off-by: Jinjie Ruan > > --- > > Documentation/admin-guide/mm/damon/reclaim.rst | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/Documentation/admin-guide/mm/damon/reclaim.rst b/Documentation/admin-guide/mm/damon/reclaim.rst > > index ec7e3e32b4ac..23fede7d1cdb 100644 > > --- a/Documentation/admin-guide/mm/damon/reclaim.rst > > +++ b/Documentation/admin-guide/mm/damon/reclaim.rst > > @@ -193,6 +193,13 @@ DAMON_RECLAIM becomes inactive, so it does nothing but periodically checks the > > watermarks. In the case, the system falls back to the LRU-list based page > > granularity reclamation logic. > > > > +To keep DAMON_RECLAIM always active regardless of the free memory rate, set > > +``wmarks_high``, ``wmarks_mid`` and ``wmarks_low`` to ``1000``, ``1000`` and > > +``0``, respectively. Then the reclamation is limited only by ``min_age`` and > > +the quotas. This is useful for reclaiming cold pages even while the system > > +has plenty of free memory, e.g., right after an idle virtual machine is > > +paused. > > + > > I feel like above might be too detailed. Particularly, the second sentence > looks too detailed. In a sense, it is not technically correct because of > 'skip_anon' parameter. We might later need to add more such controls, and I > concern if this kind of detailed documentation will limit such extensions. > > What about keeping only the first sentence and dropping later two sentences? If you don't mind, I could add this patch to damon/next after dropping the last two sentences on my own. Thanks, SJ [...]