Re: The reason to call it 3.0 is the desktop (was Re: [OT] 2.6 not3.0 - (NUMA))

Andrew Morton
2002-10-07T21:10:59Z

Linus Torvalds wrote:
>
> On 7 Oct 2002, Alan Cox wrote:
> >
> > Factoring the uid/gid/pid in actually may help in other ways. If we are
> > doing it by pid or by uid we will reduce the interleave of multiple
> > files thing you sometimes get
>
> 'pid' would probably work better than what we have now, even though I bet
> it would get confused by a large number of installers (ie "make install"
> in just about any project will use multiple different processes to copy
> over separate subdirectories. In the X11R6 tree it uses individual "cp"
> processes for each file!)
>
> The session ID would avoid some of that, but they both have a fundamental
> problem: neither pid nor session ID is actually saved in any directory
> structure, so it's quite hard to use that as a heuristic for whether a new
> file should go into the same directory group as the directory it is
> created in.
>
> That's why "uid" would work better.

Sound good to me. At leat this puts a veneer of respectability over
decapitating find_group_other(), which is really what we all want
to do anyway ;)

> The uid has a different issue, though,
> namely the fact that when user directories are created, they are basically
> always created as uid 0 first, and then a "chown" - which means that the
> user heuristic wouldn't actually trigger at the right time. So the
> heuristic couldn't be just "newfile->uid == directory->uid", it would have
> to be something better.

Last time, Al suggested that we always use the find_group_other() approach
if the directory is being made at the top-level of the filesystem. So
if /home is a mountpoint, the user directories get spread out.

I think this, and the UID comparison will be good enough.