On Tue, 13 Jul 1999 15:12:14 -0700 (PDT) 
 Matthew Dillon <dillon@apollo.backplane.com> wrote:

 >     The text size of a program is irrelevant, because swap is never
 >     allocated for it.  The data and BSS are only relevant when they
 >     are modified.

Bzzt.  BSS is relevant when accessed (at least in NetBSD).

 >     There is a lot of hidden 'potential' VM that you haven't considered.
 >     For example, if the resource limit for a process's stack is 8MB, then
 >     the process can potentially allocate 8MB of stack even though it may
 >     actually only allocate 32K of stack.  When a process forks, the child

...um, so, make the code that deals with faulting in the stack a bit smarter.

 > :* not all the world's a general purpose computing environment,
 > 
 >     Which is meaningless handwaving.  Again, you are welcome to point out
 >     your own real-life situations.

Well, I just gave you a few examples of "not a general computing environment"
in different mail.

 >     I had to deal with a reservation model on our old SGI's running 5.3
 >     for almost a year.  I know what I'm talking about and I can point to
 >     real-life cases that demonstrate it.  Certainly there are many different
 >     situations... you are welcome to bring up other real-life situations
 >     as examples.

...and as I recall, those SGIs at BEST were general-purpose computing
environments.  Chris already said that disallowing overcommit wasn't
necessarily appropriate in every situation.  So make it a knob.  Big
deal.  Everyone has what they want.

        -- Jason R. Thorpe <thorpej@nas.nasa.gov>