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=1793165073; b=cPUDNdAx0/2xohyTXO22GWd/YEVHd3cfLdjTyobgpt/nPmVo6HxnrVBA1OjpkrHKYMXh g9kWtPLBFXGTzNCIz72sdcyd5UQ2c1MG1hlpLHj4c9kNkKFduL6WoCN5pXqHGp25pu9eF SeYjQ2wQOP/TBJMkG+2o2/duPBJ1PdG5h7SQAxLtu9b+bMdfO4pVjfclcvCn18wuP8LQI UbFAylEYceIyReRVvsHGqmLo3pDcjKvdCO9RQURQHH2/MGSChqoaFsKuzLPlJs3Usfvex FMawR6DTFbPPPgdy6XDLwxY43NAlRQxQuinCYjHWlEbvnF27NVuRtirG8BfAyLOtY5A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793165073; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=oJZAZ0A86kifY1NPYX8XYC0xWNprTevsjHMyzxjeHnM=; b=0sppppXqxKv7E14ESMLDT+k1EOpOD3mUgGKsGpVUUaGf4babSK40QeEuC70woNVz7zl2 BzUD90xf4eWEmI4/yjGGzvl7Km5Eju6qJgAuIG5G6M5SG3NxAEB3OyNHt5FIGj1Vt1az7 r6Os8y/2YsgOAOStWxmXbPwh9caeQTu0mVd0CnIZO4zaaCdKgIU6oIvIqWKkXSUI8EzGX KGEtecfBNNRBfQenitVHXY3YRqzgp0XP+eKZIc/wcmXWaNMaUgsY74rCZCzmKYfm6UHq0 vz7vTSK4VO/LuwsOZo0X5yZgpb16MBPKeuorg93y8sMlcu+8WuHhTVVyrJt3wPXQ+RA== 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=ngYis3e2; 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)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F7A7606A31A; Wed, 28 Oct 2026 05:24:32 +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=ngYis3e2 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4059F1F01825; Wed, 28 Oct 2026 05:24:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793165072; bh=oJZAZ0A86kifY1NPYX8XYC0xWNprTevsjHMyzxjeHnM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ngYis3e2wvUOSJvp8+0jEGKSRDYMAK9HDAntN9cymSinu549gET696m3116YIejwJ 5XIWt/Mp+Inwhh34rmXQnFzlmSbXuxweOA+gSdcBQjRlwCxPXq6FAheBvqJqQdZzNA E4wKqnPVfaQAlZ4Q9i9McBUaVFtLkG+c7NtlMpsqccENGbmjhCiPc3cv70cYXmodue eiab7TSuTB75C1kUmYTF2sV0N6KN9Ul50EVqFwxf4RSWnUpOYVgSmnti6Ms1sTCTGr di74MpOpebIVO3Xyh3IelZ0EUD/1U+rRwUvsu+S/FEDd8MSxu6L20KJk588yv9LuGR pMMcssqoPeMDg== From: SJ Park To: Jinjie Ruan Cc: SJ Park , 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 22:24:24 -0700 Message-ID: <20261028052425.154616-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261028023628.795637-1-ruanjinjie@huawei.com> 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 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? Thanks, SJ [...]