On Sep 02, 2009 18:09 -0400, Greg Freemyer wrote: > On Wed, Sep 2, 2009 at 11:35 AM, Peng Tao<bergwolf@xxxxxxxxx> wrote: > > If we allocate the donor file once for all, it will have a better chance > > to be continuous. > > > > Signed-off-by: "Peng Tao" <bergwolf@xxxxxxxxx> > > Seems like an improvement, but I'm not seeing any special handling for > sparse files. (Not before or after this patch.) > > Seems like there should be an outer loop that identifies contiguous > data block sets in a sparse file and defrags them individually as > opposed to trying to defrag the entire file at once. > > My impression is that with a large sparse file, e4defrag currently > (with or without this patch) would fallocate a full non-sparse donor > set of blocks the full size of the original file, then swap in just > the truly allocated blocks? > > If so, that is not very optimum. And of course FIEMAP can be used to easily determine if the file is sparse. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- 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
