You can add `direct` to dd if you're concerned about the caches. And if you want to avoid seeks, just use `fallocate`. It'll do the Right Thing(tm) on CoW and n

You can add `direct` to dd if you're concerned about the caches. And if you want to avoid seeks, just use `fallocate`. It'll do the Right Thing(tm) on CoW and non-CoW filesystems - either just creating a hole or reserving extent space, without having to write all the blocks in either case.