Re: [LSF/MM TOPIC] Sparseness in storage

[Douglas Gilbert <dgilbert@interlog.com>]

On 11-02-02 09:23 PM, Christoph Hellwig wrote:
> On Wed, Feb 02, 2011 at 12:07:23PM -0500, Douglas Gilbert wrote:
>> are improving their sparseness handling as well, with Linux
>> playing "catch up" to NTFS in this regard (e.g. the new
>> FALLOC_FL_PUNCH_HOLE flag in fallocate() ).
>
> FYI: XFS has supported hole punching for more than 15 years, although
> the first years obviously were't on Linux.

I was looking at the Windows API yesterday and you need
to check each volume for sparse support. So it is file
system dependent there as well: VFAT doesn't support
sparseness and NTFS (version ?) does.

 From the perspective of user space tools, POSIX support
for sparseness would be helpful and FALLOC_FL_PUNCH_HOLE
looks like a step in that direction.

Doug Gilbert