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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 BACF9ECE58E for ; Fri, 11 Oct 2019 19:03:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90F2621835 for ; Fri, 11 Oct 2019 19:03:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20150623.gappssmtp.com header.i=@toxicpanda-com.20150623.gappssmtp.com header.b="P/Lw5TH2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728944AbfJKTDN (ORCPT ); Fri, 11 Oct 2019 15:03:13 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:34110 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728942AbfJKTDM (ORCPT ); Fri, 11 Oct 2019 15:03:12 -0400 Received: by mail-qt1-f196.google.com with SMTP id 3so15412282qta.1 for ; Fri, 11 Oct 2019 12:03:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=1zj65VAHkrvrqgSf6v62yhKJ+Twl/i9DMVLlx6+COss=; b=P/Lw5TH2CApDYV9WucqDHKN7ISqviYRM2FKKslNZUrtH+viSX+X33b853UrlmsPf8B rTJ0QBbOoQ6qSqkDKQ9vvtkMasXaAX4k4qWx28cZKhh6JHVcmlqubTTVg40B8ghKP+Nc B1iFGWCLL5qDVS3XYUJOsAR1X3kiBbo5kIWI4Y/9/37rwInGJrA0Z3GD6bsW/qi06M+q ecWHoT83DAAhdiW3p80n8DIuUKYxlIh+SPY8YGEJxXGYgqzkLyDehc6W2IVpBZ5A08Oc Bg7+axUJ13f1zDUS1qmQyoJPekISn+cA6hBQzZg3mXLw0MKChkOF7xcqvnMceGzOB3nN dpzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=1zj65VAHkrvrqgSf6v62yhKJ+Twl/i9DMVLlx6+COss=; b=PLZS5Dctp3aSAAlvMOrWy90+Y/9TxiVAZYbGb2IcdHg57FFupoDAqs5+ozbMi+nHvX uTg/iOniw2g2xixJNdXTERchBOeOW5c6KYg4crkeObpA+ZcxActOVBWhA5nOU9dDLiBc 3jadFCO3CsZWk60D21BsuDUI6bdbrhIAoxJtdBBgvWDRDyKeKtsgFaMHY0Quz+/sBP0F gFEbArHnGDjZqoOQRbbOZ9dySNT5vQSIA9JKoMlNnQB68YqlLduETXNbz2LF5tMH+IV7 baOQDcGChDGM2Zpc1dmPnPQKdgRq3hQ2lmMPW4BQXGCIOys5aU5+ohd/LOJMwd31swZU B7QA== X-Gm-Message-State: APjAAAWphoyV2H8u71q8jGqCZN6rGv7bAOw0T57BAg+vlfyvNbMRPAs4 i+KhkEoPV4Xp2ar47RYqpy8jDg== X-Google-Smtp-Source: APXvYqykqTMBbhaj+qITq53rUsWJEJASWi7o6MJhiBD5rJ4gtLZmBUVMzVLpnJofut+LtUqpLqOZqQ== X-Received: by 2002:ac8:7447:: with SMTP id h7mr18646593qtr.11.1570820590320; Fri, 11 Oct 2019 12:03:10 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::d36]) by smtp.gmail.com with ESMTPSA id z5sm4602516qtb.49.2019.10.11.12.03.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 Oct 2019 12:03:09 -0700 (PDT) Date: Fri, 11 Oct 2019 15:03:08 -0400 From: Josef Bacik To: Dave Chinner Cc: linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH V2 00/26] mm, xfs: non-blocking inode reclaim Message-ID: <20191011190305.towurweq7gsah4vr@macbook-pro-91.dhcp.thefacebook.com> References: <20191009032124.10541-1-david@fromorbit.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191009032124.10541-1-david@fromorbit.com> User-Agent: NeoMutt/20180716 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Wed, Oct 09, 2019 at 02:20:58PM +1100, Dave Chinner wrote: > Hi folks, > > This is the second version of the RFC I originally posted here: > > https://lore.kernel.org/linux-xfs/20190801021752.4986-1-david@fromorbit.com/ > > The original description of the patchset is below, the issues and > approach to solving them has not changed. THere is some > restructuring of the patch set - the first few patches are all the > XFS fixes that can be merged regardless of the rest of the patchset, > but the non-blocking reclaim is somewhat dependent of them for > correct behaviour. The second set of patches are the shrinker > infrastructure changes needed for the shrinkers to feed back > reclaim progress to the main reclaim instructure and act on the > feedback. The last set of patches are the XFS changes needed to > convert inode reclaim over to a non-blocking, IO-less algorithm. > I looked through the MM patches and other than the congestion thing they look reasonable. I think I can probably use this stuff to drop the use of the btree inode. However I'm wondering if it would be a good idea to add an explicit backoff thing for heavy metadata dirty'ing operations. Btrfs generates a lot more dirty metadata than most, partly why my attempt to deal with this was tied to using balance dirty pages since it already has all of the backoff logic. Perhaps an explict balance_dirty_metadata() that we put after all metadata operations so we have a good way to throttle dirtiers when we aren't able to keep up? Just a thought, based on my previous experiences trying to tackle this issue for btrfs, what you've done already may be enough to address these concerns. Thanks, Josef