Stuart Henderson <stu.li...@spacehopper.org> wrote:
> > Btw. there is another school of thought that says old cruft doesn't need
> > to be removed, it's not causing any harm. If you need a clean system
> > just reinstall and restore config and data from backups. It's a good
> > excercise to check that your backups are working.
>
> I disagree, it can cause harm sometimes. Not least when you run out of
> space in /usr halfway through untarring sets during an update...
That is a false history.
Many people got burned because we used to make /usr a certain size, then
we switched to clang.
But there were 2-3 other cases of this happening, where something quite big
was added to /usr
Most users upgrade release-to-release, and will only accumulate a few large
lib*.so.*.* files. The upgrade process cleans out old clang/gcc leftovers.
So there isn't much growth.
If those users upgrade via snapshots, then the library collections can become
a problem.
I think it is dangerous to push our users to use sysclean. Many of them
newbies. There are people who review the data, then
rm -rf `sysclean'
or
sysclean | xargs rm -rf
About about paths containing \n ? The lessons of find -print0 forgotten
so easily?
What about TOCTOU concerns, there is no mention of the multiuser possibility
that someone can create a path that plays with the \n concern above.
I think the program is misdesigned. It attacks files which are not in
the current upgrade set, rather than attacking files which were in
previous upgrades. It attacks non-OpenBSD files. It traverses
directories which have nothing to do with the OpenBSD system itself. It
attacks files which OpenBSD never supplied. The manual page does not
document the heuristic it will use, so that people can decide "whoa,
that will screw me because of how I use my directories". It is quite
simply unable to make correct decisions perhaps because there isn't
correct information to based this upon, and then there is this magic
leap that people won't use one of the two approaches above and after
doing so they will have a non-reversable problem. Actually probably the
biggest problems are the (1) vagueness of the manual page, assuming
people will do the right thing, and (2) people pushing (for newbies) to
use this on social media. The manual page doesn't tell people to remove.
But oh, here is a list, of what you should remove. But we didn't tell
you to remove anything. Isn't that a bit deceitful?
I've heard of experts misusing sysclean, so I very much suspect there
are many users who have misused it, destroyed their system, and been to
shy to complain.
