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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id D49C7C2BD09 for ; Tue, 9 Jul 2024 23:51:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3665B6B008A; Tue, 9 Jul 2024 19:51:04 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2EF616B0092; Tue, 9 Jul 2024 19:51:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 169316B0093; Tue, 9 Jul 2024 19:51:04 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id EC6266B008A for ; Tue, 9 Jul 2024 19:51:03 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 86B31120812 for ; Tue, 9 Jul 2024 23:51:03 +0000 (UTC) X-FDA: 82321862406.16.EF4593C Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf10.hostedemail.com (Postfix) with ESMTP id 3D6A2C0014 for ; Tue, 9 Jul 2024 23:50:59 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=DCzTmhwt; spf=none (imf10.hostedemail.com: domain of rdunlap@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=rdunlap@infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1720569045; a=rsa-sha256; cv=none; b=ymMedsUaiPbzJ9Z0ENlixE8PRNBCZI02xtB2FhPIlY2DtD/9mdn4HBkhvdGElPuxbMeKtw 4VKQyu1QLEWdg/diYXo2isIgKEb50MiM6Y6/BsYEI8ah/yGAFbVvIgJHdXBRYrpwyWsJrR 2GvtN0gnzDywUkGAulHLJ9gnF+pjoUU= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=DCzTmhwt; spf=none (imf10.hostedemail.com: domain of rdunlap@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=rdunlap@infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1720569045; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=1MnKJi0jeAHhcjlp5AtWFQ8iIjqs+OJI3rZ7gK/CmMU=; b=bNVCK1Wye8ICJFI2fSEVL+AVSkJWfl4ZEpgjgkNe+yfbgY3z9sP+BvIDEJiwI1RFzM0A9l ApfeBBLrZyhbggef+E0UFHYzkJRiANGIniBNyl2EioFBM5K02G0gGY0NiwVUanKZxqhckA gdJkqnqKjJKoqRnep4d8tbEzI9k3zRQ= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender :Reply-To:Content-ID:Content-Description; bh=1MnKJi0jeAHhcjlp5AtWFQ8iIjqs+OJI3rZ7gK/CmMU=; b=DCzTmhwt94ownkzIzPjjLO9YFf eu92ryb30Y5fTRUbNpYryFLMftlaguCeCXoN5EOazjbAsFOs+tBSCQRNU7Q9+73B6Auj6hO18pDHa tVqNTGWjeWJdyOsHdlhu3/6ety3pwwmck57aAkc4fbaq1wmZauOvq+WLqpISS8yRZqCLos8OaPI4C hs61AA6++huLcis6+2wfhFY8FKzdLoiDZGfl8hPNz2QPC/0WLP/nmKUoFVXt2uML9oLLHVZjGnISQ SNynxgD4UGwrFpzo35YzDs92U2UM4UsY3+jCn/D4vFLAhvCA1+Qv96t7MNQa7spkBp1odrX3/w5pV UYTO+k7A==; Received: from [50.53.4.147] (helo=[192.168.254.17]) by casper.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1sRKbT-00000008U6L-2tpi; Tue, 09 Jul 2024 23:50:35 +0000 Message-ID: <420ac42f-dad2-4fd9-b36a-6405d14b6e25@infradead.org> Date: Tue, 9 Jul 2024 16:50:24 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 5/9] Documentation: add a new file documenting multigrain timestamps To: Jeff Layton , Alexander Viro , Christian Brauner , Jan Kara , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Chandan Babu R , "Darrick J. Wong" , Theodore Ts'o , Andreas Dilger , Chris Mason , Josef Bacik , David Sterba , Hugh Dickins , Andrew Morton , Jonathan Corbet Cc: Dave Chinner , Andi Kleen , Christoph Hellwig , Uros Bizjak , Kent Overstreet , kernel-team@fb.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-doc@vger.kernel.org References: <20240708-mgtime-v4-0-a0f3c6fb57f3@kernel.org> <20240708-mgtime-v4-5-a0f3c6fb57f3@kernel.org> Content-Language: en-US From: Randy Dunlap In-Reply-To: <20240708-mgtime-v4-5-a0f3c6fb57f3@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: q4b6a81tb77tnbszuf5zpuox7orzay7r X-Rspamd-Queue-Id: 3D6A2C0014 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1720569059-158694 X-HE-Meta: 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 luE0GjW5 4ik1geUQHTcrQPVfpi71rkb7JRO7gs5jIMP/Kan/X3SLv8IAjC/FFpoGcv8brzlhkBtzwxpxdush9pdqbmE5hObgByWCWmxgVbppvOgFpJeugwz0lQA8isJqWhu9w/HL+e+pFmwgzT4xuSRQAaC83wPqMqnKN4nQ9mdepoTuC/6aVNlfYtp7TXk8UdSDzvX1vZVgA4aKl/wFT6vqPogVULL8ayIpP8sjKAYPMAIVGJGpZQzckeLFvnn1fi5m/eQfBINJNmbrAep1hgy34WYEVQsMwPc4dZx+/sTS++Y2aHApVLF/GVaAsda8vmg== 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: List-Subscribe: List-Unsubscribe: On 7/8/24 8:53 AM, Jeff Layton wrote: > Add a high-level document that describes how multigrain timestamps work, > rationale for them, and some info about implementation and tradeoffs. > > Signed-off-by: Jeff Layton > --- > Documentation/filesystems/multigrain-ts.rst | 120 ++++++++++++++++++++++++++++ > 1 file changed, 120 insertions(+) > > diff --git a/Documentation/filesystems/multigrain-ts.rst b/Documentation/filesystems/multigrain-ts.rst > new file mode 100644 > index 000000000000..e4f52a9e3c51 > --- /dev/null > +++ b/Documentation/filesystems/multigrain-ts.rst > @@ -0,0 +1,120 @@ > +Inode Timestamp Ordering > +======================== > + > +In addition just providing info about changes to individual files, file In addition to just > +timestamps also serve an important purpose in applications like "make". These > +programs measure timestamps in order to determine whether source files might be > +newer than cached objects.