[OpenAFS-devel] Re: AFS ... or equivalent ...

Jerry McAllister jerrymc@msu.edu
Mon, 4 Feb 2008 10:58:43 -0500


On Mon, Feb 04, 2008 at 12:58:29AM -0500, Kyle Moffett wrote:

> On Jan 16, 2008 1:48 PM, Jeffrey Hutzelman <jhutz@cmu.edu> wrote:
> > The "let's just slurp everything into the main distribution so we don't
> > have to worry about stable interfaces" approach is really poor.  It
> > encourages bad engineering practice among people maintaining the main
> > distribution, discourages innovation and extension by others, and generally
> > doesn't scale.  It's far better to either attempt to maintain stable
> > external interfaces to the VFS and VM subsystems, or else admit that you
> > don't have the resources to do so given the relatively small number of
> > external users, in which case you almost certainly also don't have the
> > resources to keep on top of updates to something like OpenAFS.
> 
> The Linux Kernel presents a very strong counter-argument-by-example.
> The amount of patches merged per released version has been linearly
> increasing over the last several years; the 2.6.23 => 2.6.24 patch was
> 49MB uncompressed, with a 5.7MB changelog.  Of that, a significant
> portion were VFS changes which touched most filesystems.  The various
> filesystem-related  changes alone between 2.6.23 and 2.6.24 were
> 2.9MB.  


So, there are reasons why many of us prefer FreeBSD to Linux.

////jerry


........
For reference, the *entire* OpenAFS diff between 2.4.6 and
> 2.5.30 is all of 8.2MB.  The Linux Kernel changes include partial
> support for having per-process views of a single filesystem
> (Specifically /proc, so /proc/net can have differing contents between
> network namespaces).  Other features which Linux supports that
> virtually no other OS does is multiple filesystem namespaces, where
> the mount-tree is selectively independent or shared between
> namespaces.
>