Christopher Kings-Lynne wrote:
>
> I seem to recall that Oracle has all sorts of fancy resource limits that can
> be applied to users. If such resource limits were implemented, then maybe
> the DBA could have the power to limit someone to a maximum of 20% cpu and a
> few transactions per second or something.
>
> Chris
I was hoping that after completing the current project I'm working
on I might be able to contribute this feature. Oracle calls them
PROFILEs which are a set of resource limits associated with a user.
They can limit:
No. of simultaneous connections
No. of blocks read per query
No. of blocks read per connection
CPU time per query
CPU time per connection
Idle time
as well as a few more esoteric others. I haven't looked at the new
system resource reporting system that Jan wrote, but I suspect some
of the statistics he gathers might already be available. Limiting
simultaneous connections by a user might take a little effort.
Limiting idle time might as well. Both have been a requested feature
in the past, but have pitfalls associated with them. But right now
denial of service for a user with database access is easy: soak up
all available connections. Like Jan's resource statistics collector,
Oracle's profiles must be enabled in the initSID.ora configuration
file since it takes a few cycles to actually account for user
activity.
Mike Mascari
mascarm@mascari.com
> > Tom Lane writes:
> >
> > > I believe the primary reason why PL languages aren't installed by
> > > default is security considerations
> >
> > Well, that argumentation seems to be analogous to giving someone login
> > access on a multiuser computer system but not letting him execute, say,
> > perl because he might write recursive functions with it. Such setups
> > exist (perhaps with something else instead of perl and recursive
> > functions) but they are not the norm and usually fine-tuned by the
> > administrator.
...
> >
> > Peter Eisentraut peter_e@gmx.net http://funkturm.homeip.net/~peter