> Hi. nice(1) is a very neat thing, but I wondered if there are
> some similar mechanisms which allow me to do the following:
> make sure no one application uses more than 30% of the CPU
Not that I know of. The design of Unix assumes that there's no point
in *not* giving cycles to even the lowest priority task, as long as
those cycles would have gone to waste anyway.
Without knowing exactly why you'd want to do this, I can't be sure
what advice will be helpful, but I suspect that the existing
login.conf(5) capabilities will avoid any particular abuse problems
you may be facing. Among other things, it lets you specify the base
priority ("nice") level for a user, as well as limits on things like
total CPU time, memory usage, and so on.
Quote:> make sure no one application uses more than 50 kb/sec in
dummynet(4) can do this. Its man page is a little terse, but it
doesn't look very hard. It uses ipfw(8) as a user interface, so you
can only apply it to things that can be recognized by that program
(which means that IP address, local user, and local group are easy,
but not really "application").