Re: Linux/Pro -- clusters

Jeff Garzik
2001-12-04T15:21:57Z

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