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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 343EDC11D27 for ; Mon, 24 Feb 2020 08:28:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EFBA20714 for ; Mon, 24 Feb 2020 08:28:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726628AbgBXI2x (ORCPT ); Mon, 24 Feb 2020 03:28:53 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:36202 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727498AbgBXI2w (ORCPT ); Mon, 24 Feb 2020 03:28:52 -0500 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01O8KMbT005409 for ; Mon, 24 Feb 2020 03:28:51 -0500 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yb161f3tg-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 24 Feb 2020 03:28:50 -0500 Received: from localhost by e06smtp02.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 24 Feb 2020 08:28:46 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01O8Sj2t52232286 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 24 Feb 2020 08:28:45 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3928C4C05C; Mon, 24 Feb 2020 08:28:45 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C94174C046; Mon, 24 Feb 2020 08:28:43 +0000 (GMT) Received: from localhost.localdomain (unknown [9.85.91.136]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 24 Feb 2020 08:28:43 +0000 (GMT) From: Chandan Rajendra To: Amir Goldstein Cc: linux-xfs@vger.kernel.org, Allison Collins Subject: Re: [PATCH v7 00/19] xfs: Delayed Ready Attrs Date: Mon, 24 Feb 2020 14:01:35 +0530 Organization: IBM In-Reply-To: References: <20200223020611.1802-1-allison.henderson@oracle.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-TM-AS-GCONF: 00 x-cbid: 20022408-0008-0000-0000-00000355D847 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20022408-0009-0000-0000-00004A76EFDC Message-Id: <2644091.QCrdQm5Jf7@localhost.localdomain> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-24_02:2020-02-21,2020-02-24 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 clxscore=1015 bulkscore=0 impostorscore=0 adultscore=0 phishscore=0 malwarescore=0 mlxscore=0 suspectscore=5 mlxlogscore=999 lowpriorityscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002240073 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Sunday, February 23, 2020 1:25 PM Amir Goldstein wrote: > On Sun, Feb 23, 2020 at 4:06 AM Allison Collins > wrote: > > > > Hi all, > > > > This set is a subset of a larger series for delayed attributes. Which is > > a subset of an even larger series, parent pointers. Delayed attributes > > allow attribute operations (set and remove) to be logged and committed > > in the same way that other delayed operations do. This allows more > > complex operations (like parent pointers) to be broken up into multiple > > smaller transactions. To do this, the existing attr operations must be > > modified to operate as either a delayed operation or a inline operation > > since older filesystems will not be able to use the new log entries. > > High level question, before I dive into the series: > Hi Amir, My 2 cents on this topic (Assuming "delayed operations" refer to "deferred ops") ... > Which other "delayed operations" already exist? static const struct xfs_defer_op_type *defer_op_types[] = { [XFS_DEFER_OPS_TYPE_BMAP] = &xfs_bmap_update_defer_type, [XFS_DEFER_OPS_TYPE_REFCOUNT] = &xfs_refcount_update_defer_type, [XFS_DEFER_OPS_TYPE_RMAP] = &xfs_rmap_update_defer_type, [XFS_DEFER_OPS_TYPE_FREE] = &xfs_extent_free_defer_type, [XFS_DEFER_OPS_TYPE_AGFL_FREE] = &xfs_agfl_free_defer_type, }; > I think delayed operations were added by Darrick to handle the growth of > translation size due to reflink. Right? So I assume the existing delayed > operations deal with block accounting. IIRC, Deferred ops are meant to not violate the AG locking order. If AG 'x' metadata block[s] is locked then we can only lock metadata blocks of AGs starting from 'x+1'. Transactions can return -EAGAIN when they detect that they need to lock metadata blocks belonging to AG 'x-1' or less. In such a case the transaction will be rolled during which the locks on metadata blocks are given up. > When speaking of parent pointers, without having looked into the details yet, > it seem the delayed operations we would want to log are operations that deal > with namespace changes, i.e.: link,unlink,rename. > The information needed to be logged for these ops is minimal. > Why do we need a general infrastructure for delayed attr operations? > > Thanks, > Amir. > > > > -- chandan