From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B0B0C2D0DB for ; Wed, 29 Jan 2020 17:24:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2E9382070E for ; Wed, 29 Jan 2020 17:24:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ZLc73rJZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2E9382070E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BC1346B0275; Wed, 29 Jan 2020 12:24:39 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B712A6B0276; Wed, 29 Jan 2020 12:24:39 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A86546B0277; Wed, 29 Jan 2020 12:24:39 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0170.hostedemail.com [216.40.44.170]) by kanga.kvack.org (Postfix) with ESMTP id 9425D6B0275 for ; Wed, 29 Jan 2020 12:24:39 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 541B7180AD804 for ; Wed, 29 Jan 2020 17:24:39 +0000 (UTC) X-FDA: 76431346278.23.sleep65_62cbfd02ed23e X-HE-Tag: sleep65_62cbfd02ed23e X-Filterd-Recvd-Size: 3838 Received: from mail-ed1-f51.google.com (mail-ed1-f51.google.com [209.85.208.51]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Wed, 29 Jan 2020 17:24:38 +0000 (UTC) Received: by mail-ed1-f51.google.com with SMTP id c26so556851eds.8 for ; Wed, 29 Jan 2020 09:24:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=GuZW6M/lHdLlpFsrtgMOqn+Z8lIxB/V7NcObC/beNbQ=; b=ZLc73rJZzZhkR5KlqUoD+Vwg/rJZAPHOv0FC+mm7okKRdACPtHYQwr2TPUCjvfwCDm 4P3dWvoFQUdwrf095nZ3oiiksPX8hJ/RNQekNg7rbc74d7zswE6rS1XP5DP/jUvg8F8/ Ca9qfZEKQn2J4hBLL7P7V0erMa3UVH4ti1vmRMdde4ycWb3MjiYW1r/3yTVbNqAU1oNF gkOhLwTV2BR0JtAstphkNo0ZEP32Whtp9H14l/KsulmzkrgvZq3c+6W+xHIZKaK8g7Du IrkAzuk1GYpag34budpY0yoEdVr4W3OTE5/u2OzHE5D60PQVa8PQelJFFrVt8hcZXyUF DHIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=GuZW6M/lHdLlpFsrtgMOqn+Z8lIxB/V7NcObC/beNbQ=; b=Lufm0GwVn1FNUMr7O3YQov0ZczQK/lSlVcQAco6no0YNibCeUFP+BDZUGd6w333euh ZSBAmlQGfYbKLpd5EnXYNweVLgET6IzaYe4+oHWsmGJOnIS8htlCze0iyAAXL5PPHfex B69Rx3TX2Tm8kDF9emhSSlIvbK7RtorC9dbvDTCKvEjTu+6LM5KkFvcqtMcirFvz30kt KorBa3dgJiQW9DD2ZX4stcHs+qjf58yhtwYxZhZW6cBqze4m3dMCy9G5hflV0oNhP6rH PEGGHbMI1pSiGi7b0/OEL20GCnGR1dHqHs9PGwDWRC7q1ZjgCRJGvri8gSilFIdO4V7b LfVQ== X-Gm-Message-State: APjAAAUzKdz7OgSc8lEE1tvtdXEZLCqrGKYNVu+XaqTNEJCNShOkSi6V F6QZrKTCB+HMygl5PZy5hpIPTMz9i5+DN+EuQew= X-Google-Smtp-Source: APXvYqxHCze/xW7n7FUIwJbNcr78LHRnZWfg9J/GO+AImp9HBnbDvsZZXXL/88T42+NmfEzNH7c7HK1c8SN6x3RA9FM= X-Received: by 2002:a17:906:4e46:: with SMTP id g6mr404211ejw.309.1580318677028; Wed, 29 Jan 2020 09:24:37 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Yang Shi Date: Wed, 29 Jan 2020 09:24:24 -0800 Message-ID: Subject: Re: [LSF/MM/BPF TOPIC] Memory Tiering discussion To: Dave Hansen Cc: lsf-pc@lists.linux-foundation.org, Linux MM , Michal Hocko , Dan Williams , Mel Gorman , Dave Hansen , Yang Shi Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Jan 28, 2020 at 4:05 PM Dave Hansen wrote: > > On 1/28/20 11:50 AM, Yang Shi wrote: > > So I would like to discuss how we should move forward, what pieces we > > still miss, what we can combine, etc. > > Thanks for proposing this! > > In addition to what you've mentioned, I'd really like to close in on > what folks think the first set of patches we _merge_ would look like. > More features than what we've got in the two sets? Less? Good point. We'd better figure out the minimal viable set. > > I'd also like to have to rehash a few discussions we've had inside > Intel. For instance, migrating (demoting) a page cache page is more That would be definitely useful. > expensive than just discarding at reclaim time. But, it might be > expensive to recreate that page later if we do discard it. There > doesn't seem to be a single, obviously "right" answer. I agree, so my patchset just deals with anonymous pages. Page cache seems more tricky.