From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Vicentiu Neagoe" Subject: Re: resilience against power loss Date: Mon, 28 Jul 2014 18:23:11 +0300 Message-ID: <53D66ADF.14170.351043D9@vicentiu.neagoe.ni.com> References: <53CE9282.11182.166B0034@vicentiu.neagoe.ni.com>, Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE To: linux-ext4@vger.kernel.org Return-path: Received: from skprod3.natinst.com ([130.164.80.24]:57882 "EHLO ni.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751046AbaG1PXP (ORCPT ); Mon, 28 Jul 2014 11:23:15 -0400 Received: from us-aus-mgwout1.amer.corp.natinst.com (nb-chan1-1338.natinst.com [130.164.19.134]) by us-aus-skprod3.natinst.com (8.14.5/8.14.5) with ESMTP id s6SFNCdj004521 for ; Mon, 28 Jul 2014 10:23:13 -0500 In-reply-to: Sender: linux-ext4-owner@vger.kernel.org List-ID: On 28 Jul 2014 at 10:48, Luk=E1s Czerner wrote: > On Tue, 22 Jul 2014, vicentiu.neagoe@ni.com wrote: >=20 > > Date: Tue, 22 Jul 2014 19:34:10 +0300 > > From: vicentiu.neagoe@ni.com > > To: linux-ext4@vger.kernel.org > > Subject: resilience against power loss > >=20 > > Hello, > >=20 > > I'm trying to configure ext4 to prevent data corruption in case of = a=20 > > power loss. > >=20 > > I test by doing a cold reset right after writing to a file. > > I tried the nodelalloc option, but the file still becomes corrupted= =20 > > with trailing garbage. > >=20 > > Using ext3, I either get the old version of the file, or the new=20 > > version, and there is no corruption. > >=20 > > Does nodelalloc not guarantee data integrity? > >=20 > > Are there any other options that provide complete resilience agains= t=20 > > power loss? >=20 > Well, that would be fsync. It'll make sure that your data actually re= ach > disk and that the disk actually write it from the cache to platters. I don't have control over how the applications were written, yet I=20 need the system to not corrupt or lose data in case of a power loss. I have the partition mounted with the sync option but the issue still=20 reproduces. Are there no options on ext4 to provide the same data integrity as=20 data=3Dordered on ext3? I also tested with Btrfs and there is no data=20 corruption on a power loss. Vicentiu > -Lukas >=20 > >=20 > > thanks > >=20 > > Vicentiu > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-ext= 4" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > >=20 > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html