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=-2.2 required=3.0 tests=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 3ECEECA9ED0 for ; Sun, 3 Nov 2019 21:26:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1D6D821D80 for ; Sun, 3 Nov 2019 21:26:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727771AbfKCV0z (ORCPT ); Sun, 3 Nov 2019 16:26:55 -0500 Received: from mail104.syd.optusnet.com.au ([211.29.132.246]:57966 "EHLO mail104.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727501AbfKCV0z (ORCPT ); Sun, 3 Nov 2019 16:26:55 -0500 Received: from dread.disaster.area (pa49-180-67-183.pa.nsw.optusnet.com.au [49.180.67.183]) by mail104.syd.optusnet.com.au (Postfix) with ESMTPS id 539D743F213; Mon, 4 Nov 2019 08:26:51 +1100 (AEDT) Received: from dave by dread.disaster.area with local (Exim 4.92.3) (envelope-from ) id 1iRNOc-0006Rt-MU; Mon, 04 Nov 2019 08:26:50 +1100 Date: Mon, 4 Nov 2019 08:26:50 +1100 From: Dave Chinner To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 04/26] xfs: Improve metadata buffer reclaim accountability Message-ID: <20191103212650.GA4614@dread.disaster.area> References: <20191009032124.10541-1-david@fromorbit.com> <20191009032124.10541-5-david@fromorbit.com> <20191030172517.GO15222@magnolia> <20191030214335.GQ4614@dread.disaster.area> <20191031030658.GW15222@magnolia> <20191031205049.GS4614@dread.disaster.area> <20191031210551.GK15221@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191031210551.GK15221@magnolia> User-Agent: Mutt/1.10.1 (2018-07-13) X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.2 cv=G6BsK5s5 c=1 sm=1 tr=0 a=3wLbm4YUAFX2xaPZIabsgw==:117 a=3wLbm4YUAFX2xaPZIabsgw==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=kj9zAlcOel0A:10 a=MeAgGD-zjQ4A:10 a=7-415B0cAAAA:8 a=HdJPOkImENtfvV1LZcUA:9 a=CjuIK1q_8ugA:10 a=biEYGPWJfzWAr4FL6Ov7:22 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Archived-At: List-Archive: List-Post: On Thu, Oct 31, 2019 at 02:05:51PM -0700, Darrick J. Wong wrote: > On Fri, Nov 01, 2019 at 07:50:49AM +1100, Dave Chinner wrote: > > On Wed, Oct 30, 2019 at 08:06:58PM -0700, Darrick J. Wong wrote: > > > > In the case of the xfs_bufs, I've been running workloads recently > > > > that cache several million xfs_bufs and only a handful of inodes > > > > rather than the other way around. If we spread inodes because > > > > caching millions on a single node can cause problems on large NUMA > > > > machines, then we also need to spread xfs_bufs... > > > > > > Hmm, could we capture this as a comment somewhere? > > > > Sure, but where? We're planning on getting rid of the KM_ZONE flags > > in the near future, and most of this is specific to the impacts on > > XFS. I could put it in xfs-super.c above where we initialise all the > > slabs, I guess. Probably a separate patch, though.... > > Sounds like a reasonable place (to me) to record the fact that we want > inodes and metadata buffers not to end up concentrating on a single node. Ok. I'll add yet another patch to the preliminary part of the series. Any plans to take any of these first few patches in this cycle? > At least until we start having NUMA systems with a separate "IO node" in > which to confine all the IO threads and whatnot . :P Been there, done that, got the t-shirt and wore it out years ago. IO-only nodes (either via software configuration, or real cpu/memory-less IO nodes) are one of the reasons we don't want node-local allocation behaviour for large NUMA configs... Cheers, Dave. -- Dave Chinner david@fromorbit.com