On 2012-02-05, at 10:23 AM, Eric Sandeen wrote:
> On 2/5/12 10:55 AM, Andreas Dilger wrote:
>> On 2012-02-05, at 9:36, Eric Sandeen <sandeen@xxxxxxxxxx> wrote:
>>> On 2/5/12 3:33 AM, Ron Yorston wrote:
>>>> Eric Sandeen wrote:
>>>>> Now that ext4, xfs, & ocfs2 can support punch hole, a tool to
>>>>> "re-sparsify" a file by punching out ranges of 0s might be in order.
>>>>>
>>>>> I'll see if util-linux wants it after it gets beat into shape.
>>>>> (or did a tool like this already exist and I missed it?)
>>>
>>> Matthias' suggestion of adding SEEK_HOLE/SEEK_DATA makes very good sense
>>> too.
>>
>> I thought about this, but if SEEK_HOLE/SEEK_DATA (or FIEMAP) worked,
>> then the file would already be sparse, so I don't think that will
>> help in this case...
>
> But only if other tools originally used them, and there will probably be
> plenty
> of cases where they don't, or legacy files, or ....
I was thinking that the suggestion was to use SEEK_HOLE/SEEK_DATA to find
the holes in the file... Of course, it makes a lot of sense if you use
them to skip the existing holes, and only look for strings of zeros in the
data parts...
Cheers, Andreas
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