Scrub free disk blocks

[Patrick O'Callaghan]

On Sat, 2010-08-28 at 07:42 -0700, JD wrote:
> > However note that neither of these methods guarantees to scrub
> indirect
> > blocks in the filesystem that were used to create the space-filling
> > files. Maybe they do, maybe they don't, it's not clear.
> >
> > poc
> >
> Very good.
> Actually, indirect blocks are used if and only if the file is larger
> than what can be addressed via direct blocks.
> So, scrub has no interest in whether or not a file has indirect
> blocks, nor should it care if blocks are direct or indirect.
> During file access, the file system will access ANY file block(s)
> that the process has the right permissions for.

So what? My point is that after scrubbing and removal of the
space-filling files, you may be left with a number of sectors that were
used for indirect blocks during the space-filling phase of the scrub
process. These sectors may not themselves be scrubbed but will now be
available on the free list after you're done.

poc