Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Kristof Provost <kristof@codepro.be>
Newsgroups: comp.os.linux.development.system
Subject: Re: shred or scrub
Date: Fri, 18 Apr 2014 14:42:14 +0000 (UTC)
Organization: A noiseless patient Spider
Lines: 13
Message-ID: <slrnll2ea9.2p2.kristof@vega.codepro.be>
References: <limvgj$tse$1@dont-email.me> <slrnlkvkrl.2p2.kristof@vega.codepro.be> <liqmp7$4md$1@dont-email.me>
Injection-Date: Fri, 18 Apr 2014 14:42:14 +0000 (UTC)
Injection-Info: mx05.eternal-september.org; posting-host="c4bb3d93ef445461fe1a8177e331b545"; logging-data="26952"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX19LVa1vPOGMt2d0hv+3TnwadV5SonsqNEM="
User-Agent: slrn/1.0.1 (FreeBSD)
Cancel-Lock: sha1:9E4xY3tK1UfGrv3JHsiT+OQRWmU=
Xref: csiph.com comp.os.linux.development.system:627

On 2014-04-18, crankypuss <crankypuss@nomail.invalid> wrote:
> On 04/17/2014 07:15 AM, Kristof Provost wrote:
>> That's because there's no way to guarantee that the file system will
>> write the new data over the same block as the old data. In fact, in
>> log-structured file systems (like ZFS, but not ext3/4) the file system
>> will deliberately not do this.
>
> That seems very messed up.

Aside from the data safety point it also makes implementing snapshots
really easy and efficient.

Kristof