From nobody Wed Oct 8 12:39:23 2025 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 89D9625D549; Sat, 28 Jun 2025 16:51:58 +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=1751129518; cv=none; b=k4GwMQ8VLC2nhpbZQqgyoWOKtbJaDVAdRBJ/tEUXWFmBNVPN/wMo2W7lrKBEHZQZcAUnnBiaANT8R2BkpGwTCFSCru1jgTe/DMrN0IbK0lNKicb/wamCh6OyGpBm0XkN8sa6zmJj2i3h1WKY354zbB3yjOJyUCMv49ST3p5BTJ0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751129518; c=relaxed/simple; bh=tlvqxxIUDAypcpXix4DDUce9Gvf8SrIMBmaTGFZI30U=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XQiQyIX1g8f4iwHxJpNwodAYPjel3Xki7EwNLJppsfV18Kcqlls15iXJYX6/Okh2cwFB8tOn94scxm+fSY675uWhJg3JrCX3J5ny4+is1Ip8jb8DNm4Aqifi9xVDnu72XYJMPOYWJbiunCYyWH03EpiuXNLK1dsHULSs3699rMM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lgLtLZ6q; 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="lgLtLZ6q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 405D1C4CEED; Sat, 28 Jun 2025 16:51:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751129518; bh=tlvqxxIUDAypcpXix4DDUce9Gvf8SrIMBmaTGFZI30U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lgLtLZ6q9JHyXcZE7E3djoYPOZN6LsoO2UhZ5uv5R40j+Kt/aTRhT71X+TgkdBMWc epy51+h6/a+DXlMCvZwjFGaoVr7BNrO9FmPkC95JSnXO5SxX1FE3V7vH7IwNHCUTvy CU1DpW+/553Is8RvXDBb82W4sPBn39AuMfLcZjVD/SQtayqs6319uJuCl+erCXEqpz 7l8usr6qm4bB3L0l2/V6L8WiP/t8ZiRRWuNwy8lKA2HB88I0Omf4IEEt06p7CD/tEj tflx4ALke51tN6w42QYzk5kVHblMRp8csfEYwWLcX/rQavPWGKArTWqJ9Q/4g15EDm X+5qNzFqaRMDQ== From: SeongJae Park To: Cc: SeongJae Park , Andrew Morton , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 10/11] mm/damon/lru_sort: add monitoring intervals auto-tuning parameter Date: Sat, 28 Jun 2025 09:51:43 -0700 Message-Id: <20250628165144.55528-11-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250628165144.55528-1-sj@kernel.org> References: <20250628165144.55528-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 99c5a22cf3f2..1e9e19f15b33 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); =20 +/* + * Auto-tune monitoring intervals. + * + * If this parameter is set as ``Y``, DAMON_LRU_SORT automatically tune + * DAMON's sampling and aggregation intervals. The auto-tuning aims to ca= pture + * meaningful amount of access events in each DAMON-snapshot, while keepin= g the + * sampling interval 5 milliseconds in minimu, and 10 seconds in maximum. + * Setting this as ``Y`` disables the auto-tuning. + * + * Disabled by default. + */ +static bool autotune_monitoring_intervals __read_mostly; +module_param(autotune_monitoring_intervals, bool, 0600); + /* * Filter [none-]young pages accordingly for LRU [de]prioritizations. * @@ -261,6 +275,7 @@ 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; @@ -269,18 +284,27 @@ static int damon_lru_sort_apply_parameters(void) if (err) return err; =20 - err =3D damon_set_attrs(ctx, &damon_lru_sort_mon_attrs); + attrs =3D damon_lru_sort_mon_attrs; + if (autotune_monitoring_intervals) { + attrs.sample_interval =3D 5000; + attrs.aggr_interval =3D 100000; + attrs.intervals_goal.access_bp =3D 40; + attrs.intervals_goal.aggrs =3D 3; + attrs.intervals_goal.min_sample_us =3D 5000; + attrs.intervals_goal.max_sample_us =3D 10 * 1000 * 1000; + } + err =3D damon_set_attrs(ctx, &attrs); if (err) goto out; =20 err =3D -ENOMEM; - hot_thres =3D damon_max_nr_accesses(&damon_lru_sort_mon_attrs) * + hot_thres =3D damon_max_nr_accesses(&attrs) * hot_thres_access_freq / 1000; hot_scheme =3D damon_lru_sort_new_hot_scheme(hot_thres); if (!hot_scheme) goto out; =20 - cold_thres =3D cold_min_age / damon_lru_sort_mon_attrs.aggr_interval; + cold_thres =3D cold_min_age / attrs.aggr_interval; cold_scheme =3D damon_lru_sort_new_cold_scheme(cold_thres); if (!cold_scheme) { damon_destroy_scheme(hot_scheme); --=20 2.39.5