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... > I should also untie the read/zero buffer size from the minimum hole size, > we should do optimal IO sizes regardless of the minimum hole size desired... Definitely. 4kB IO is a killer for large files. Cheers, Andreas-- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
