this is correct. in general, the filesystem repairing aside, dump will always just visit blocks that are referenced in the filesystem.
for example, if you have 0 dirty blocks and then temporarily create 100MB file and then delete it *before* it is dumped. then you got 100MB of dirty blocks in the cache. these blocks will not be cleaned out by dump as the blocks are not referneced in the filesystem. these blocks belong to no files but are chained in the free list. these blocks are not lost. they will be used when allocating storage for files. if these files get dumped, the dirty pool shrinks. -- cinap
