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Date: Fri, 11 Feb 2005 02:14:28 -0800
From: Andrew Morton <akpm@osdl.org>
To: Junfeng Yang <yjf@stanford.edu>
Cc: linux-kernel@vger.kernel.org, mc@cs.Stanford.EDU
Subject: Re: [CHECKER] Does sys_sync (ext2, 2.6.x) flush metadata?
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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?

It should be.

>  I've gotten many "error" traces for ext2, where
> directory entries are not flushed to disk after sys_sync.

How?

>  In other words,
> even if users do call sys_sync, a crash after sys_sync call can still
> cause file losses.  Is this intended?

No.