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Tue May 19 16:20:27 PDT 1998

For legal reasons the two active files for using Soft Updates are in
/usr/src/contrib/sys/softupdates. To enable the feature in your kernel,
link the files into this directory as follows:

	cd /usr/src/sys/ufs/ffs
	ln -s ../../../contrib/sys/softupdates/*.[ch] .

and add option SOFTUPDATES to your kernel configuration.  You should also
read the copyrights in the sources and the README file in
/usr/src/contrib/sys/softupdates before enabling this feature to ensure
that you are acting legally. The stub file provided here is only enough
to allow the system to function without this option being turned on.

WARNING: RE-DISTRIBUTING A KERNEL WITH SOFTUPDATES COMPILED IN WITHOUT
DISTRIBUTING THE SOURCE TO THE _ENTIRE_ KERNEL IS NOT PERMITTED.  See the
copyright on the soft update files, or ../../../contrib/sys/softupdates/README

Once you're running a kernel with soft update support, you need to enable
it for whichever filesystems you wish to run with the soft update policy.
This is done with the -n option to tunefs(8) on the UNMOUNTED filesystems,
e.g. from single-user mode you'd do something like:

	tunefs -n enable /usr

To permanently enable soft updates on the /usr filesystem (or at least
until a corresponding ``tunefs -n disable'' is done).

IMPORTANT NOTE:  The Soft Updates code is currently in ALPHA test.
Use at your own risk!

For more general information on soft updates, please see:
	http://www.ece.cmu.edu/~ganger/papers/CSE-TR-254-95/

--
Julian Elischer <julian@freebsd.org>
OpenPOWER on IntegriCloud