From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F24D43939AF; Tue, 13 Jan 2026 15:27:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768318054; cv=none; b=NBftNOoIFwkwPxDcuFbP4XyPVdp+U+LQD7HeyGkE+xVtS1Aj2+baoO+DChdzOrtwKSBSDcvbg5Dc+wefXy0WR6wQJjmrSx6GP6dce28cLYUBLWEM4jL5UKADmBqoLZj6up/qCtejPniHztzgBrlB+WuSTSWylPmzo/YNl5UdNc0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768318054; c=relaxed/simple; bh=f3S6xDzMYwBAJsmHW3zullLbXTgyY6fprlw1+nJamAA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DMpcxzjW+C/UvXL2KlftxTClNp9H5ZnEGXnMMVd6t9vTgGawKHvA6s8OvmYuB4hxastimcgwbXjXn/l3Gy7vCJqN17v0YdFqzP0IqBmqoNY4L11kYr/YvP65xOD8Bdm3h6MaQOIl9HXk2M7W6BTKATGurN5CA2GayVl3qDvUHdQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BU7j9M+T; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BU7j9M+T" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 963CBC19424; Tue, 13 Jan 2026 15:27:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768318053; bh=f3S6xDzMYwBAJsmHW3zullLbXTgyY6fprlw1+nJamAA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BU7j9M+T12Pl2/6y/ThZgQsOBqc2tov7ik5qihZ+zekXx4nv/okg1SjeyuMJKE8ct UrrJK6PnCIRHTrzVLUx8eLaLQqYzPFlZRzqi0VP+0oPaXA6dcPAmoxzpwVvDUxRPc3 ZYkXjvDj37yDuO31Wj5O2XtCX47hiyIIh1/NIfE3vQz5BlKMHaafY/I/y3p6NdQFaZ nwnwNdhHh5cJ4WyEhhHDDu8V0GHAqm0sj4jzdyThuvafKvoZpu214Q3E+edJaqqcGL uqbxEceh/bVlsT6G7KOQYkYBBJQUXcIRGQ2nwvCDZqV64YiKPprYbLvO+nN6mdeN9B PU1b4lvH3tbVQ== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 10/11] mm/damon/lru_sort: add monitoring intervals auto-tuning parameter Date: Tue, 13 Jan 2026 07:27:15 -0800 Message-ID: <20260113152717.70459-11-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260113152717.70459-1-sj@kernel.org> References: <20260113152717.70459-1-sj@kernel.org> Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit DAMON monitoring intervals tuning was crucial for every DAMON use case. Now there are a tuning guideline and an automated intervals tuning feature. DAMON_LRU_SORT is still using manual control of intervals. Add a module parameter for utilizing the auto-tuning feature with a suggested auto-tuning parameters. Signed-off-by: SeongJae Park --- mm/damon/lru_sort.c | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c index f3a9dfc246b6..717cc585d207 100644 --- a/mm/damon/lru_sort.c +++ b/mm/damon/lru_sort.c @@ -55,6 +55,20 @@ module_param(commit_inputs, bool, 0600); static unsigned long active_mem_bp __read_mostly; module_param(active_mem_bp, ulong, 0600); +/* + * Auto-tune monitoring intervals. + * + * If this parameter is set as ``Y``, DAMON_LRU_SORT automatically tunes + * DAMON's sampling and aggregation intervals. The auto-tuning aims to capture + * meaningful amount of access events in each DAMON-snapshot, while keeping the + * sampling interval 5 milliseconds in minimum, and 10 seconds in maximum. + * Setting this as ``N`` disables the auto-tuning. + * + * Disabled by default. + */ +static bool autotune_monitoring_intervals __read_mostly; +module_param(autotune_monitoring_intervals, bool, 0600); + /* * Filter [non-]young pages accordingly for LRU [de]prioritizations. * @@ -268,6 +282,7 @@ static int damon_lru_sort_apply_parameters(void) { struct damon_ctx *param_ctx; struct damon_target *param_target; + struct damon_attrs attrs; struct damos *hot_scheme, *cold_scheme; unsigned int hot_thres, cold_thres; int err; @@ -290,18 +305,27 @@ static int damon_lru_sort_apply_parameters(void) goto out; } - err = damon_set_attrs(param_ctx, &damon_lru_sort_mon_attrs); + attrs = damon_lru_sort_mon_attrs; + if (autotune_monitoring_intervals) { + attrs.sample_interval = 5000; + attrs.aggr_interval = 100000; + attrs.intervals_goal.access_bp = 40; + attrs.intervals_goal.aggrs = 3; + attrs.intervals_goal.min_sample_us = 5000; + attrs.intervals_goal.max_sample_us = 10 * 1000 * 1000; + } + err = damon_set_attrs(param_ctx, &attrs); if (err) goto out; err = -ENOMEM; - hot_thres = damon_max_nr_accesses(&damon_lru_sort_mon_attrs) * + hot_thres = damon_max_nr_accesses(&attrs) * hot_thres_access_freq / 1000; hot_scheme = damon_lru_sort_new_hot_scheme(hot_thres); if (!hot_scheme) goto out; - cold_thres = cold_min_age / damon_lru_sort_mon_attrs.aggr_interval; + cold_thres = cold_min_age / attrs.aggr_interval; cold_scheme = damon_lru_sort_new_cold_scheme(cold_thres); if (!cold_scheme) { damon_destroy_scheme(hot_scheme); -- 2.47.3