The struct buf junta met...

[Poul-Henning Kamp]

The struct buf junta met at an undisclosed location, and this is what
we found out:

With the 5-stable branch (still) being 3-4 in the future, we want
to get as much as the API changes into the stable branch as possible,
in order to not do another "3.x mistake".

The things you can expect to see appearing (provided we can make it
work) is:

1.  Move floppies & CD's under GEOM.

2.  Move the vcount() to the dev_t for VCHR.
    This removes one icky problem from vnode locking.

3.  Vnode bypass for userland device access.
    This is the stuff I posted a prototype of some time ago:  Go directly
    from the filedesc switch to SPECFS thus bypassing vnodes and vnode
    locking intirely and going Giant-free for drivers that support this.

4.  Scatter/Gather mapped/unmapped struct bio.
    This allows an I/O request to be composed of a number of pages spread
    out in physical memory.

5.  Shoot pbufs
    In swap_pager.c, vfs_cluster, spec_getpages, AIO, O_DIRECT...

We have a lot of ideas going forward from that point, but they are
not concrete enough to actually formulate as a plan yet.

We will try to explain this coherently at the devsummit this weekend
and in email subsequent to that.



Secretary for the Buf Junta

Poul-Henning
-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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Never attribute to malice what can adequately be explained by incompetence.