looking towards 2.4

[Erik Arjan Hendriks]

On Tue, Nov 21, 2000 at 05:10:04PM -0500, Rob Latham wrote:
> Has anyone considered porting bproc to the 2.4 kernels?  I realize
> they are in a rather mushy feature freeze, but they've got to be close
> to releasing 2.4 soon, right?

Not really.  2.4 has been "close" for a long time.  ("show me the
money")  My time is currently very limited so I'm not planning to even
look at doing that until 2.4 is out and deemed stable enough for
serious use.  (Flakiness on a single box is sometimes tolerable in
light of new features, etc.  Flakiness on a single box times 128 boxes
in a cluster is never tolerable.)
 
> As far as bproc is concerned, have the changes to the process table
> been as dramatic as those done to the network driver interface?  Will
> a port be a matter of a few tweaks or will it require a redesign?

The port will be more than a few tweaks but a redesign shouldn't be
required.  While the process table stuff is basically unchanged
(AFAIK) there was been a lot of churning in the VM and VFS code.
Also, with finer grained locking there are probably a lot more locks
to worry about.

The process memory space dumper will probably have to change a bit.
All of the kernel/user space interface code will have to change
significantly.  Most of the other code will be reusable but the
addition of locks will require me to go over the whole thing and think
about locks again.  If they're as undocumented as they are in 2.2.x,
it will take good deal of time to get all the lock stuff debugged.
 
- Erik
-- 
Erik Arjan Hendriks          Printed On 100 Percent Recycled Electrons
hendriks@scyld.com                 Contents may settle during shipment