Bill, I think you didn't read what I write so here is it again: My applications are VMs. Every disk that you give to a VM is zeroed out, one way ot the other: One way is to use dd or something that has the same effect the other is using a sparse file. That is guranteed. Now as soon as you start working in this VM it is not guranteed because on real live applications it makes limited sense to zero out freed blocks (expect maybe you have a SAN LUN exported from a storage device that supports data deduplication or if you want that deleted files disappear from you block device). Todays datadeduplication and backupsolutions for VM depend on the property that unused data blocks are zeroed out. And actually I can't think of an easier interface. As I proposed earlier, if you don't like it for performance reasons, that's fine, but if you have to backup 5.6 Terabyte instead of 17 Terabyte than this is a huge space safer even with the performance overhead involved. Thomas -- 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