On Tue, 13 Jun 2000, Richard Gooch wrote:
> > Richard, may I remind you that we are supposed to be in the freeze?
> > There may be a chance to trim the union down _and_ get it into 2.4.
>
> ??? Didn't you read the other parts of my message. Quoting myself:
>
> > Besides, there's also the problem of getting efficiency improvements
> > into the mainline kernel. I don't expect Linus would let us fix these
> > things so close to 2.4.
Let me put it that way: odds of getting conceptually very simple _and_
doable on per-fs basis changes into the tree are much, much better than
doing that with the overhaul of fs/namei.c and all revalidate code, may it
be damned. Yes, revalidate() is the last sucking part of VFS-proper. Yes,
we will need to do that. But doing that _now_? Yeah, right.
> And here you quote me:
> > > Yeah, but 2.4 is too close. Such a change is going to require a fair
> > > bit of surgery for all filesystems.
>
> So I don't really expect wholesale VFS changes right now (but, hey,
> that doesn't seem to stop you getting stuff in;-). But that shouldn't
They would not be there if not for your ability to get devfs there ;-/
And took three months of piece-wise feeding the fixes into tree.
> stop us talking about where to go from here.
> > You don't need it on all filesystems.
>
> So you're thinking of attacking just the worst offenders?
If we have, e.g. UFS and ext2 taken care of (in that sequence - scratch
monkey first) the rest will be doable essentially at leisure. Changes to
a filesystem are local to that filesystem and do not affect the rest - the
only infrastructure problem had been solved in 2.3.1. So IMO it's
proof-of-concept + several worst offenders to drive the size down + the
rest during 2.4 whenever somebody has spare time. Doing that in one huge
patch? No, thanks.
> OK, so you're assuming that shrinking the union will be done by only
> attacking a small number of filesystems. In that case, it will
> probably be less invasive that splitting the dcache and icache.
> However, ultimately I'd like to see the union thrown out entirely.
As soon as it shrinks to zero elements...
> And also have the dcache and icache split.
In the main tree - not earlier than 2.5. It should either be done right or
not at all and doing it right is way too late for 2.4.
