RE: Samba

["Kevin Musick" <kmusick@teldar.com>]

Roland:

Thanks for the quick response.  I fully understand the lack of available
development resources.  I also think that for the Hurd to be truly usable in
today's heterogenous computing environments it must deal with the ubiquity
of Microsoft's operating systems.  I am not experienced enough with Hurd
architecture to develop any conceptual blueprint, but given such a plan I
would be willing to work on it.  Two of my colleagues are interested in Hurd
development as well.

>From a humble user's perspective, I would like to see the following:

1.  Support for Samba (i.e. file locking)
2.  The ability to obtain device specific information, such as disk
geometry.  This would correct the fdisk problem and, more importantly, make
possible a Hurd installation utility that allows for the management of drive
partitions.
3.  Changing the way Hurd maps a drive partition, to allow for larger
volumes.  (I understand some of this has been done, and is in a separate CVS
branch.)
4.  Corrections to the NFS server, which I have heard tends to lock under
duress.

I'm also curious about microkernel architecture.  I've worked with Mach
quite a bit, and in general I support its use with the Hurd.  I also know
that, in a multiserver environment, the number of IPC messages required
decreases performance, because each message operation involves an expensive
context switch.  MIT developed an "exokernel" a few years back, which
essentially provided only an abstraction of the underlying hardware, leaving
most traditional operating system services left to execute in user space.
Wouldn't it be theoretically possible to implement Mach's process
management, memory management, and IPC mechanisms as some form of protected
programs running in user space on top of this "exokernel?"  I'm not asking
anyone to work on this, or even look into it.  I'm just curious if such an
approach even sounds plausible.

By the way, I understand it is a Hurd convention to make /usr a symbolic
link to /.  May I ask why?

Kevin Musick
kmusick@teldar.com


-----Original Message-----
From: Roland McGrath [mailto:roland@frob.com]
Sent: Saturday, May 27, 2000 3:29 PM
To: Kevin Musick
Cc: debian-hurd@lists.debian.org
Subject: Re: Samba


There is not much in the way of file locking available in the Hurd, and in
particular we do not have facilities that match the POSIX semantics for
fcntl locking, or (I think) the BSD semantics for flock.  The specified
semantics are not very elegant from a component-model perspective, and thus
nontrivial to design Hurd protocols to properly support.  We (the core Hurd
developers) have discussed some ideas for new Hurd RPCs for locking, but
never fully resolved on a plan and the main issue is that noone has had the
time to make it a priority thing to work on.  If there is active interest
by someone who will do the implementation work, then I think we can manage
to dig up our thoughts on the issue and figure out a good way to go about
it.  But I don't know when any of the core Hurd developers might have the
time to actually do such an implementation.