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Message-ID: <58cb370e050211051752d0342c@mail.gmail.com>
Date: Fri, 11 Feb 2005 14:17:49 +0100
From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reply-To: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
To: Junfeng Yang <yjf@stanford.edu>
Subject: Re: [CHECKER] Does sys_sync (ext2, 2.6.x) flush metadata?
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       mc@cs.stanford.edu
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Hi,

On Thu, 10 Feb 2005 23:59:53 -0800 (PST), Junfeng Yang <yjf@stanford.edu> wrote:
> 
> Hi,
> 
> We're working on a file system checker and have a question regarding what
> sys_sync actually does.  It appears to us that sys_sync should sync both
> data and metadata, and wait until both data and metadata hit the disk
> before it returns.  Is this true for all the file systems (especially
> ext2) for kernel 2.6.x?  I've gotten many "error" traces for ext2, where
> directory entries are not flushed to disk after sys_sync.  In other words,
> even if users do call sys_sync, a crash after sys_sync call can still
> cause file losses.  Is this intended?

I don't know what exactly you are doing but do you remember
about disabling write caching on your disks in case of doing
real hard crashes?

Regards,
Bartlomiej