From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.gmx.net (mout.gmx.net [212.227.15.15]) (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 22FA72C82 for ; Tue, 30 Nov 2021 12:51:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1638276675; bh=c9z8o/iWr3NTfj+uUiO32jPRashfLcZ877UxpLrEltA=; h=X-UI-Sender-Class:Subject:From:To:Cc:Date:In-Reply-To:References; b=YU7up95ZwBXzYuR8k8mB8ZU5cS4Mhh7bYzhx4ccIkEknE6hS2PnasdsOgZKG5aVkY 5Z+k0dEqvOlYcHWwyjJ3X7Kjz+nErO7i9nUmZdm/cn2wgDCvhCdgTtF63IJA0ab/hl 20QkWptII5d3lWkfL9JjpKcv06/hWHoy33Dt/cR8= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from homer.fritz.box ([185.146.50.175]) by mail.gmx.net (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1M2wL0-1mt8071500-003OtP; Tue, 30 Nov 2021 13:51:15 +0100 Message-ID: Subject: Re: [PATCH 1/1] mm: vmscan: Reduce throttling due to a failure to make progress From: Mike Galbraith To: Mel Gorman Cc: Alexey Avramov , Andrew Morton , Michal Hocko , Vlastimil Babka , Rik van Riel , Darrick Wong , regressions@lists.linux.dev, Linux-fsdevel , Linux-MM , LKML Date: Tue, 30 Nov 2021 13:51:10 +0100 In-Reply-To: References: <20211125151853.8540-1-mgorman@techsingularity.net> <20211127011246.7a8ac7b8@mail.inbox.lv> <20211129150117.GO3366@techsingularity.net> <20211130112244.GQ3366@techsingularity.net> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.1 Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:HGsRl3HDz3scVmthJ3IF67/Ifz7L1wEt0wBJNxdAE66j4O51TJj CV/qBcer3kOWf/oLFhFopDmDwk2da2kkHHsOak13Tzxd37MpvBsG1+TjjMS396/Ba0FeQpk rdYboQvmOBzs585YMviW9F6z/jM3bbBWeaauok14z9VLWIN/9mqbO5Fomj1n+m0xwHnqVMq 48nMw0GY7KRlgi/11aAfA== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:5qzsiGktCB4=:0UIvHvh15dzuz76ASShWyz U+XO5AyMH4hJnuX5sjDsRAHlVit+8S1etVLADZ8Dw2sZPERBNDtZoH/a4HX9IttVDgRM4SheD sYerLEROsnHKFlRB9gPc4IhetRk1Ep9ujrTGAlysqwLVtfwXFxCxMAO3N2Ze8TrRKTV+0r3Fp a18OtQ1Vpm+21qZpfS/U0Gsco1sPDQeNPFposDeQeEsbs+5m5f4rJBaOY3p+uH2NI8bWEQV42 aVTYF9o6aIhw7mVzuMbuV9wFM2YSCeXReZnybFy0vZxhMwS1SJ4Wa12L9TAT0xTu7On+/s3IX VXHI8vof63+k5vHTRltKTOUHWeMZ5wT5HLbXDw4tIQhcxMMJ50StMFHXeTFdbVUIDgIzoh0xd /z/nQhDKKFkMDZUP5ti7wt1dy2PT+sUKDW9pbO/Ovuj02HAnI6/EE+yGtRE03gCk65yACwNsa fx6iuMlL5/wbw9hylcR1xfCsi4yh/D5HPFH73WdIyOePVcyyWgBQD93bV75ksipEHWxqmn+2t y452xX1xY4ag41vLvpvbK/qNg5BeHpVs4jFXmrFRQzrk6OvHTo7eIxliKlg+FMtpmFDh7xOPk XJRTthZ6rH/uZXgPSxhGlcsAowt6ZyuYoODJt2Zm5I1npCe+NoqS8XeTVFrFTiC7NnQ5dt5zR emOadZQksoIVxG2ZZOuNdWBrWO+MhWJtzYQstQxnW+W9bDdPuo/E3W7/uLMGyVrojBC45N6rw 0fPTjMSej6VFGdmSxFB4OU2hXNvVzGCHlwrtIveJXf3nIP0i4s3IbZJlN56uPPEGE2hgT9stW VFSz6TxOk8WCmKtPBYNpt1Gv+xNKKO1cGOGglHdGB6WFnb9vJkMwMBZdqdQQOo/QA2UghYM/9 HB9/8PlHZGqXw2faArBxPEy2/DFhw/M3tbKmzGJsKAQ0uL+wtBQGGHFhXQ2RcCuw5a049qzx4 2rOv2DpYYR/O2UEr8gjX1WnYqDP2T2GZ4bPS3XaQ+3Fo1Fj4dz+LqSEjyOPwjVSVXjtxyEXze r+6Kr+jeQ0npAYROVZ0/lWbb/81arMpZnxk8UiJJl8q3XukPatpPwVLaeIi14Psdt9UIsOMcs shUtYLeNCJLJy8= On Tue, 2021-11-30 at 13:00 +0100, Mike Galbraith wrote: > On Tue, 2021-11-30 at 11:22 +0000, Mel Gorman wrote: > > On Tue, Nov 30, 2021 at 11:14:32AM +0100, Mike Galbraith wrote: > > > > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0} > > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0if (2 * write_pending <= =3D reclaimable) > > > > > > That is always true here... > > > > > > > Always true for you or always true in general? > > "Here" as in the boxen located at my GPS coordinates :) > > > The intent of the check is "are a majority of reclaimable pages > > marked WRITE_PENDING?". It's similar to the check that existed prior > > to 132b0d21d21f ("mm/page_alloc: remove the throttling logic from the > > page allocator"). > > I'll put my trace_printk() back and see if I can't bend-adjust it. As it sits, write_pending is always 0 with tail /dev/zero. -Mike