From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outbound-smtp01.blacknight.com (outbound-smtp01.blacknight.com [81.17.249.7]) (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 8E30E2C80 for ; Tue, 30 Nov 2021 17:34:08 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail02.blacknight.ie [81.17.254.11]) by outbound-smtp01.blacknight.com (Postfix) with ESMTPS id 1D42BC4B13 for ; Tue, 30 Nov 2021 17:27:56 +0000 (GMT) Received: (qmail 22121 invoked from network); 30 Nov 2021 17:27:55 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[84.203.17.29]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 30 Nov 2021 17:27:55 -0000 Date: Tue, 30 Nov 2021 17:27:54 +0000 From: Mel Gorman To: Alexey Avramov Cc: Andrew Morton , Michal Hocko , Vlastimil Babka , Rik van Riel , Mike Galbraith , Darrick Wong , regressions@lists.linux.dev, Linux-fsdevel , Linux-MM , LKML Subject: Re: [PATCH 1/1] mm: vmscan: Reduce throttling due to a failure to make progress Message-ID: <20211130172754.GS3366@techsingularity.net> References: <20211125151853.8540-1-mgorman@techsingularity.net> <20211127011246.7a8ac7b8@mail.inbox.lv> <20211129150117.GO3366@techsingularity.net> <20211201010348.31e99637@mail.inbox.lv> Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20211201010348.31e99637@mail.inbox.lv> User-Agent: Mutt/1.10.1 (2018-07-13) On Wed, Dec 01, 2021 at 01:03:48AM +0900, Alexey Avramov wrote: > I tested this [1] patch on top of 5.16-rc2. It's the same test with 10 tails. > > - with noswap > > Summary: > > 2021-11-30 23:32:36,890: Stall times for the last 548.6s: > 2021-11-30 23:32:36,890: ----------- > 2021-11-30 23:32:36,891: some cpu 3.7s, avg 0.7% > 2021-11-30 23:32:36,891: ----------- > 2021-11-30 23:32:36,891: some io 187.6s, avg 34.2% > 2021-11-30 23:32:36,891: full io 178.3s, avg 32.5% > 2021-11-30 23:32:36,891: ----------- > 2021-11-30 23:32:36,892: some memory 392.2s, avg 71.5% > 2021-11-30 23:32:36,892: full memory 390.7s, avg 71.2% > > full psi: > https://raw.githubusercontent.com/hakavlad/cache-tests/main/516-reclaim-throttle/516-rc2/patch5/noswap/psi > > mem: > https://raw.githubusercontent.com/hakavlad/cache-tests/main/516-reclaim-throttle/516-rc2/patch5/noswap/mem > Ok, taking just noswap in isolation, this is what I saw when running firefox + youtube vido and running tail /dev/zero 10 times in a row 2021-11-30 17:10:11,817: ================================= 2021-11-30 17:10:11,817: Peak values: avg10 avg60 avg300 2021-11-30 17:10:11,817: ----------- ------ ------ ------ 2021-11-30 17:10:11,817: some cpu 1.00 0.96 0.56 2021-11-30 17:10:11,817: ----------- ------ ------ ------ 2021-11-30 17:10:11,817: some io 0.24 0.06 0.04 2021-11-30 17:10:11,817: full io 0.24 0.06 0.01 2021-11-30 17:10:11,817: ----------- ------ ------ ------ 2021-11-30 17:10:11,817: some memory 2.48 0.51 0.38 2021-11-30 17:10:11,817: full memory 2.48 0.51 0.37 2021-11-30 17:10:11,817: ================================= 2021-11-30 17:10:11,817: Stall times for the last 53.7s: 2021-11-30 17:10:11,817: ----------- 2021-11-30 17:10:11,817: some cpu 0.4s, avg 0.8% 2021-11-30 17:10:11,817: ----------- 2021-11-30 17:10:11,817: some io 0.1s, avg 0.2% 2021-11-30 17:10:11,817: full io 0.1s, avg 0.2% 2021-11-30 17:10:11,817: ----------- 2021-11-30 17:10:11,817: some memory 0.3s, avg 0.6% 2021-11-30 17:10:11,817: full memory 0.3s, avg 0.6% Obviously a fairly different experience and most likely due to the underlying storage. Can you run the same test but after doing this $ echo 1 > /sys/kernel/debug/tracing/events/vmscan/mm_vmscan_throttled/enable $ cat /sys/kernel/debug/tracing/trace_pipe > trace.out and send me the trace.out file please? -- Mel Gorman SUSE Labs