[Lustre-devel] moving /proc to $MNT/.lustre

[Andreas Dilger]

On Jan 07, 2008  13:10 -0500, Brian J. Murrell wrote:
> On Mon, 2008-01-07 at 09:50 -0800, Nathan Rutman wrote:
> > well, that's why I asked.  As I said, Andreas and I are in agreement, 
> > and it certainly makes sense from a portability point of view, as well 
> > as consistency with future features (snapshots, audit logs, etc.), and 
> > the final elimination of our various /proc locking headaches.  But yes, 
> > it would break user's scripts  - that's a 1-time thing, and I think not 
> > too terrible.
> 
> Is it possible to support both for a release or two to give people time
> to migrate and have an actual implementation to test against as they
> work to port their scripts?  The alternative is that given that we don't
> provide public beta binaries or nightly snapshot binaries, we'd be
> requiring people who want to port, test and release their ports on "flag
> day" to build from CVS to test.

It wasn't mentioned here, but this is already planned.  There will be
new commands "lctl get_param" and "lctl set_param" (or similar) that
will be usable by scripts to get/set Lustre tunables.  This will work
with both /proc and .../.lustre files so will allow scripts to move
over to the new mechanism.

For user-space servers there will be no alternative but to use the lctl
mechanism since /proc entries will not exist at all.  Then again, there
will not be any existing systems using the old mechanism since uOSS will
only work with ZFS.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.