Summary: Do you run Unix without disk quotas?

[Daniel Packman]

No doubt the best way to manage disk space depends on what the users are
doing at each site.  Here each user needs some "fixed" disk space for
programs and small data files.  For running the programs, the user needs
large amounts of disk space (from several megabytes to several hundred
megabytes).

The straightforward way to manage this is via quotas in a "HOME" area
governing the "fixed" disk space and no quotas on a large scratch area.

My system of preference (to be built) uses hard disk quotas on all disk
areas with no area oversubscribed.  This way no program (or user) can
inadvertantly fill up a partition.  The management system will give the
user a certain amount of fixed space in a set of partitions and will
dynamically allocate space on other partitions on request.  The dynamically
allocated space (through either a command interface or library call) is
managed through the system-wide disk quota system.  The user requests so
much space for so much time.  If allowed, the space is guaranteed for
that time.  The user may then specify that a set of his files in this
dynamic area are valuable and cannot be destroyed.  These files are then
migrated automatically to offline media (eg, tape) before that disk area
is freed and his quota automatically reduced.  Files not so marked are
assumed scratch and are deleted after the agreed upon time limit expires
and disk space is needed.