Re: Linux/Pro -- clusters

[Jeff Garzik <jgarzik@mandrakesoft.com>]

Daniel Phillips wrote:
> 
> On December 4, 2001 03:09 am, Donald Becker wrote:
> > To bring this branch back on point: we should distinguish between
> > design for an arbitrary and unpredictable goal (e.g. 128 way SMP)
> > vs. putting some design into things that we are supposed to already
> > understan
> >    [...]
> >    a VFS layer that doesn't require the kernel to know a priori all of
> >      the filesystem types that might be loaded
> 
> Right, there's a consensus that the fs includes have to fixed and that it
> should be in 2.5.lownum.  The precise plan isn't fully evolved yet ;)
> 
> See fsdevel for the thread, 3-4 months ago.  IIRC, the favored idea (Linus's)
> was to make the generic struct inode part of the fs-specific inode instead of
> the other way around, which resolves the question of how the compiler
> calculates the size/layout of an inode.
> 
> This is going to be a pervasive change that someone has to do all in one
> day, so it remains to be seen when/if that is actually going to happen.
> 
> It's also going to break every out-of-tree filesystem.

ug.  what's wrong with a single additional alloc for generic_ip?  [if a
filesystem needs to do multiple allocs post-conversion, somebody's doing
something wrong]

Using generic_ip in its current form has the advantage of being able to
create a nicely-aligned kmem cache for your private inode data.

	Jeff


-- 
Jeff Garzik      | Only so many songs can be sung
Building 1024    | with two lips, two lungs, and one tongue.
MandrakeSoft     |         - nomeansno