> I noticed that you didn't mention the file system type. The effects of
> file system type and layout of the subject instance is an often
> overlooked contributor to performance in operations which are
> mass-populating the file system, as a restoral will. A journaled file
> system can exhibit a lot of overhead as its journal is written with at
> least metadata, depending upon type; and an ill-located journal can
> make for a lot of disk arm diversions during the restoral, aggravating
> elapsed time.

The output file system was Ext2, which is not journalled.