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 1DE4F2C21DC for ; Sun, 21 Sep 2025 21:27:09 +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=1758490029; cv=none; b=DoY8a82uVqrfM/a/rJ6pjJv4/LfQyj5TmxEWAAMe6x+NF0949GrZYeXC4n+tjtJQk73belZuvDKReuq2Hn509BA5o/cxwMYNBeApkLTImuD/NNhmXw/aplmEsqUXjW3gkEdBBRju+aOyzZqVvDwPseEfZHPa7Lmh72Nbq6zh+6U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758490029; c=relaxed/simple; bh=0mrOT9SJVzsyfuSTfVvcXviMnW05mKAM6pNmduthsE0=; h=Date:To:From:Subject:Message-Id; b=hqcVdshyJeSlvf7xfcGJsFkYEUdMfSYacJsUvyPcBXFBXWLhGZpjdlRNhWBv21jntLZp0LcIAr94ejZBKO1PJlA1xxSqPc/O92YqTP/sOLN/EmCMBW4zCERcGwgEZwFF+/72ZeyX1K9/lD97LXK7Nf4qGAvHr1i8FHJOJSm0N8c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=fs+8/0zp; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="fs+8/0zp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA830C4CEE7; Sun, 21 Sep 2025 21:27:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1758490029; bh=0mrOT9SJVzsyfuSTfVvcXviMnW05mKAM6pNmduthsE0=; h=Date:To:From:Subject:From; b=fs+8/0zpUndW0BaMuvAHmWhch9p8/kZ/gJmDJoucJheXey3m6d9JAjYmaJcKQUEty /PcbXEsPLqJPkeBAekUJO62CrIzAU63orLvloRNkuEB8sIlIXFR97Sq2sPN3TPTY1T 1dGa6+e0YzmprtJ40UlfiJxWhR6M5QNPnVSvdAIk= Date: Sun, 21 Sep 2025 14:27:08 -0700 To: mm-commits@vger.kernel.org,sj@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-damon-stat-expose-the-current-tuned-aggregation-interval.patch removed from -mm tree Message-Id: <20250921212708.EA830C4CEE7@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/damon/stat: expose the current tuned aggregation interval has been removed from the -mm tree. Its filename was mm-damon-stat-expose-the-current-tuned-aggregation-interval.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: SeongJae Park Subject: mm/damon/stat: expose the current tuned aggregation interval Date: Tue, 16 Sep 2025 11:31:26 -0700 Patch series "mm/damon/stat: expose auto-tuned intervals and non-idle ages". DAMON_STAT is intentionally providing limited information for easy consumption of the information. From production fleet level usages, below limitations are found, though. The aggregation interval of DAMON_STAT represents the granularity of the memory_idle_ms_percentiles. But the interval is auto-tuned and not exposed to users, so users cannot know the granularity. All memory regions of non-zero (positive) nr_accesses are treated as having zero idle time. A significant portion of production systems have such zero idle time. Hence breakdown of warm and hot data is nearly impossible. Make following changes to overcome the limitations. Expose the auto-tuned aggregation interval with a new parameter named aggr_interval_us. Expose the age of non-zero nr_accesses (how long >0 access frequency the region retained) regions as a negative idle time. This patch (of 2): DAMON_STAT calculates the idle time for a region as the region's age multiplied by the aggregation interval. That is, the aggregation interval is the granularity of the idle time. Since the aggregation interval is auto-tuned and not exposed to users, however, users cannot easily know in what granularity the stat is made. Expose the tuned aggregation interval in microseconds via a new parameter, aggr_interval_us. Link: https://lkml.kernel.org/r/20250916183127.65708-1-sj@kernel.org Link: https://lkml.kernel.org/r/20250916183127.65708-2-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton --- mm/damon/stat.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/mm/damon/stat.c~mm-damon-stat-expose-the-current-tuned-aggregation-interval +++ a/mm/damon/stat.c @@ -39,6 +39,11 @@ module_param_array(memory_idle_ms_percen MODULE_PARM_DESC(memory_idle_ms_percentiles, "Memory idle time percentiles in milliseconds"); +static unsigned long aggr_interval_us; +module_param(aggr_interval_us, ulong, 0400); +MODULE_PARM_DESC(aggr_interval_us, + "Current tuned aggregation interval in microseconds"); + static struct damon_ctx *damon_stat_context; static void damon_stat_set_estimated_memory_bandwidth(struct damon_ctx *c) @@ -133,6 +138,7 @@ static int damon_stat_damon_call_fn(void return 0; last_refresh_jiffies = jiffies; + aggr_interval_us = c->attrs.aggr_interval; damon_stat_set_estimated_memory_bandwidth(c); damon_stat_set_idletime_percentiles(c); return 0; _ Patches currently in -mm which might be from sj@kernel.org are mm-damon-sysfs-set-damon_ctx-min_sz_region-only-for-paddr-use-case.patch