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=1793196493; b=YNLE4vsr0Dk72InRk/LoeQaJfIAyjPCPlrW7/FoTzNvkXYCvGJruZlHFwzsQON3ydwrn COkNZDQ4LVXT0++bgVsC/tV8rAXTtm3KPJlxys+mgOVhcbvYkQgYHwPioxmWvgP7iDx73 losgo9Iu/YO+aKH/wTSRml9xu2SSNIWPzaRjfWj5Jr74WQilnV9XHnRIP9W0Wer2idI0E 5R5mRLgpp4I0lH3dBzHJXItNs/xD7lsBE0csJVK5KBe+8vYpIPfOvmXQjqEm0w5IWwvaz T+LERgqyBiLQEQ6lAGTdOlrNoRxHElF/QZu1ozAEw6bH5YZtrgzAAFUjCGHdP0F6ORg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793196493; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=qRZx+uCzjDXnaggv9NA2GtraDXmEHwAiGFLHgafIj5E=; b=RAZiXWjNYrQCtBwt8p7xYJZ9EkZSWnTyVlOjcW2dV5zjTH/0ELd8R1uHnsEkNmmbqblF +jPVAPNcJ7jPqPHiQFoHsAB4a4Uw8q4exAnNGWActI1S59fnGyFh7xwqIaXxBocB/w+0e giQVVkpxAhDdsVtbKsv4Hy7sDoRHBcg2fSIUR9eGn6PDPc+7u2V+3uR6ekqH9MHaujZbK 0UxYcxpvlzAGOCr+hM0y1HeU/n3FgjEhB6aRrGDNioects89wDYUmdeN6lFNT5a+HAkc2 9OlccVhfapp9O7g+9S2O8nowh+ThHCyxoODKVhamwjSOGI0jiQOy0YF90tLXZngVMFQ== 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=JjrDrAWL; 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 E71FC606A31A; Wed, 28 Oct 2026 14:08:12 +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=JjrDrAWL Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E72C1F01825; Wed, 28 Oct 2026 14:08:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793196492; bh=qRZx+uCzjDXnaggv9NA2GtraDXmEHwAiGFLHgafIj5E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=JjrDrAWLTDPsAUrZN+XPbqZ7cfing5M98T3onac6DKid6Qut5cw1320CJkeX4nD0u Ukbu5Ugwyx1bjDn0dOwA1Ev/LBOIW4TE6G48P/ZRhfHcx47w9Wg8NhhyQdAtClTw1/ dXiquSva30A28GxPycrfHJoY9YBvSHy4ObLysaizJdTgYa5VRICt83OZF9bIxisNkU LH2lkfoFucpK6GUtB+0kkk+JB0T/e9v04zuEgNt9JxcDAfPQrFxQkpads/0BNR3fQx K5HcZ+O0PfwyAkuRuGn3VgoaRWCZK1cqd0h3/Dq9zDyvaCYYchTRFqcUxdFr/EkL3I 2ysaDSNlGZltw== 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: Wed, 28 Oct 2026 07:08:03 -0700 Message-ID: <20261028140805.159912-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On Wed, 28 Oct 2026 14:09:39 +0800 Jinjie Ruan wrote: > > > 在 2026/10/28 13:35, SJ Park 写道: > > 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 Reviewed-by: SJ Park > >>> --- > >>> 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. > > Hi SJ, > > It is fine with me, thanks. Please go ahead. Thank you for accepting my suggestion. I applied this patch to damon/next [1] with my suggested change. I will repost it for mm.git merge next week. So, no action from your side is needed for now. If it seems I also forgot doing that or you cannot wait for my action, please feel free to ping me or Andrew. [1] https://origin.kernel.org/doc/html/latest/mm/damon/maintainer-profile.html#scm-trees Thanks, SJ [...]