svn commit: r244663 - stable/9

[Benjamin Kaduk]

On Sat, Dec 29, 2012 at 5:44 AM, Robert N. M. Watson <rwatson at freebsd.org>wrote:

> When we talked to various VFS maintainers, looked at the past change
> history there, and looked at the set of third-party file systems
> (especially, those we could see in ports), the consensus there was that it
> was too difficult to define a stable VFS KPI and KBI for third-party
> modules. In particular, there appear to be at most one or two in ports at
> any given moment, and quick analyses of them suggested that their kernel
> feature dependency footprint was far more than just "vnode operations".


If OpenAFS is the only out-of-tree filesystem in ports, then most
definitely there are far more dependencies in place.  I don't know how
closely Isilon's stuff keeps to our models, though I do seem to recall that
at least their style guide has some differences from ours.

At the devsummit in 2011 in Ottawa, I did go through and look up what
kernel changes had caused a need for the OpenAFS module to be recompiled on
the stable branches, and I think most of them were not really VFS-related,
but rather networking related.  (I no longer have the list handy, sadly.)

-Ben