xfs
[Top] [All Lists]

Re: XFS DMAPI file I/O

To: James A Goodwin <jagoodwi@xxxxxxxxxx>
Subject: Re: XFS DMAPI file I/O
From: Steve Lord <lord@xxxxxxx>
Date: 02 Jan 2002 10:53:26 -0600
Cc: linux-xfs@xxxxxxxxxxx
In-reply-to: <OFE7E4F040.2F2B0E0B-ON86256B35.005BF678@xxxxxxxxxxxxxxx>
References: <OFE7E4F040.2F2B0E0B-ON86256B35.005BF678@xxxxxxxxxxxxxxx>
Sender: owner-linux-xfs@xxxxxxxxxxx
On Wed, 2002-01-02 at 10:53, James A Goodwin wrote:
> I have two questions about I/O using the Linux XFS DMAPI implementation:
> 
> 1. Some filesystems store a little bit of the file data in the i-node.
> This results in the first X bytes staying resident even after a
> dm_punch_hole command tries to free them.  Is this the case with XFS, and
> if so, how many bytes are stored this way?

There is never any file data in the xfs inode - the original data
structures allowed for it, but it was never implemented. Things like
mmap etc probably got too nasty.

> 
> 2. I just noticed that the DM_WRITE_SYNC flag is not supported for calls to
> dm_write_invis().  This is a fairly critical piece of missing
> functionality.  Is there any chance this flag may be implemented in the
> future?  I am currently porting a DMAPI application from another platform,
> and this could cause some major problems.


Dean will have to answer that one.

Steve

> 
> Thanks,
> 
> -James Goodwin
> Software Engineer
> IBM Global Services - Federal
> jagoodwi@xxxxxxxxxx
> Phone: (281) 336 2578
> Fax: (281) 335 4231
> T/L 260-2578
-- 

Steve Lord                                      voice: +1-651-683-3511
Principal Engineer, Filesystem Software         email: lord@xxxxxxx


<Prev in Thread] Current Thread [Next in Thread>