From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Vladimir V. Saveliev" Subject: Re: [PATCH] fix problems related to journaling in Reiserfs Date: Thu, 01 Sep 2005 11:47:11 +0400 Message-ID: <4316B1FF.6000008@namesys.com> References: <6.0.0.20.2.20050831191551.03fdbac0@129.60.53.12> <43164523.7030301@lab.ntt.co.jp> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <43164523.7030301@lab.ntt.co.jp> List-Id: Content-Type: text/plain; charset="us-ascii" To: Hifumi Hisashi Cc: michael chang , reiserfs-dev@namesys.com, reiserfs-list@namesys.com Hello Hifumi Hisashi wrote: > michael chang wrote: > >> Surely we don't want this. Look at the papers on Namesys's websites, >> about the atomicaty and the banking example. But that's just my >> personal opinion. Besides, I believe it's more likely that usually >> the power gets lost than the SCSI or IDE cable gets disconnected, >> AFAIK... >> >> > A write() syscall with the O_SYNC flag must ensure that not only > file data block > but also journal (meta-data update) are written to a disk when this > syscall end. yes > But, current implementation of Reiserfs does not do that. If a system > crashes, > a filesystem recovers from the journal transaction log. There is nothing wrong that reiserfs replays journal after system crash. But, Reiserfs > may not > recover in some cases. Well, we used to think that reiserfs's O_SYNC support works. It is very surprising that it does not. > I checked other filesystems like ext3, jfs, xfs. Those filesystem > write transactions > to a disk everytime write() with the O_SYNC is performed. In those > filesystem, > I have no trouble mentioned above. > > I should say, the Reiserfs would be "un"reliable filesystem.......... > > >