On Mon, 29 Jun 1998 00:53:05 +1000 
 a.robbie@student.unimelb.edu.au (Andrew J Robbie) wrote:

 > I also have some swap/VM questions :-)

And we have answers!!  :-)

 > Is it possible to use files as secondary swap partitions in NetBSD? Reading
 > the swapctl man pages isn't very informative. It would be really good for
 > flexability reasons, esp if the swap file could grow as needed. Perhaps this
 > is available with UVM?

It's available in 1.3 with Mach VM, and -current with Mach VM and UVM.
you can specify any regular file as a swap "device".  The file will not
grow, but you can add more as you need them.

e.g.:

	dd if=/dev/zero of=/swapfile0 bs=1k count=32k
	swapctl -a /swapfile0

 > Also, is it possible to have something like the tempfs under Solaris? Is
 > this what an mfs file system does?

Yes, here is how I configure it on my SPARC:

swap       /tmp            mfs     rw,-s=32768     0 0

...that creates a 16M /tmp using the memory file system.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                            Home: +1 408 866 1912
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