Subject: None
To: Jonathan Stone <>
From: Chris G Demetriou <Chris_G_Demetriou@BALVENIE.PDL.CS.CMU.EDU>
List: tech-kern
Date: 11/21/1995 21:40:44
> [Apparently], Frank van der Linden <>  writes:
> >> The main problem is, that the VM system does not know about the existance
> >> of the I/O buffer cache.k
> cgd replies:
> >hah.  you can work around that.
> >the main problem is that if you malloc() (sizeof RAM) + (sizeof swap),
> >the system will crash.

i actually meant to say "and touch all the pages" too, but...  8-)

> Tommyrot.  Balderdash.  Try running "tail -f" on an NFS-mounted filesystem.
> (How does one work around  that?)

by not using NFS?  the fact is, while NFS is bloody useful, you can
get by without using it in many environments.  (*chuckle* and some
would say "you should.")

by fixing tail?  the problem is cause by the fact that tail uses mmap,
and other mmap-using programs (like 'cat') have been changed to not
use it, to avoid just this problem!

in no environment is the system safe from the "out of space" problem.
Also, the "out of space" problem will easily crash -- actually, not
even crash, just hang -- a machine, which means that it's very, very
useful for denial of service...