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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 88A0DC3A5A4 for ; Fri, 30 Aug 2019 08:08:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 579532173E for ; Fri, 30 Aug 2019 08:08:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="VHOTeZlm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727960AbfH3IIV (ORCPT ); Fri, 30 Aug 2019 04:08:21 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:58262 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726978AbfH3IIV (ORCPT ); Fri, 30 Aug 2019 04:08:21 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7U86esp132121; Fri, 30 Aug 2019 08:08:17 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : subject : to : references : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2019-08-05; bh=dWl+95zeAqRGZtXcoLCRBaO3HhMktrMTA2iCjDOv0zk=; b=VHOTeZlmS1UJ+IlwQtAr6BVhaSmAh5Z9iN5UFSg9zmWJeTTuCp1WeVeD5vadvdT1Oft5 KdmHi8pMjbr4Df8/MWForpBuCwlfU+CHw95DV+54hZ6sDAQPrxU62ou2amKrf2/cytb1 bkFmu647UFQl1TvptRVTv7rDMGLoA0xPCmpGfiO31WMS2CSWF9iUwMsPvP/xOkoerKAq DC/tsYQKYX/KXyU74HFdjkQeRAqqXk9nYy2/D30kK7Fl/CAUuIV8EshiMlcmxVaskTZ3 xTQMocFfZCNzlCY9T6Gc4H2s3KUXa5FDvqCMZn9aNSkM6h6xBmAC/LbQ1HsLTABuHFX4 zw== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by userp2120.oracle.com with ESMTP id 2uq009g0c4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 30 Aug 2019 08:08:17 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7U83Cqb137260; Fri, 30 Aug 2019 08:07:38 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3020.oracle.com with ESMTP id 2upkrg0hk2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 30 Aug 2019 08:07:38 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x7U87WvQ024474; Fri, 30 Aug 2019 08:07:32 GMT Received: from [10.190.130.61] (/192.188.170.109) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 30 Aug 2019 01:07:31 -0700 From: Anand Jain Subject: Re: Spare Volume Features To: Marc Oggier , linux-btrfs@vger.kernel.org References: <0b7bfde0-0711-cee3-1ed8-a37b1a62bf5e@megavolts.ch> Message-ID: <32719c3e-6aa5-940f-6d53-59bab80d5ad5@oracle.com> Date: Fri, 30 Aug 2019 16:07:28 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <0b7bfde0-0711-cee3-1ed8-a37b1a62bf5e@megavolts.ch> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9364 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908300086 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9364 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908300086 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org use-cases in production must need a spare device to maintain data redundancy in the event of volume disk failure, so this feature should be in btrfs.ko. And nntil we get there, workaround like monitor for write_io_errs and call for replace should help. HTH. Thanks, Anand