Re: My project wish-list for the next 12 months

Scott Long wrote:
> 5.  Clustered FS support.  SANs are all the rage these days, and
> clustered filesystems that allow data to be distributed across many
> storage enpoints and accessed concurrently through the SAN are very
> powerful.  RedHat recently bought Sistina and re-opened the GFS source
> code, so exploring this would be very interesting.

There are certain steps that can be be taken one at a time.  For example
it should be relatively easy to mount snapshots (ro) from more than one
machine.  Next step would be to mount a full 'rw' filesystem as 'ro' on
other boxes.  This would require cache and sector invalidation broadcasting
from the 'rw' box to the 'ro' mounts.  The holy grail of course is to mount
the same filesystem 'rw' on more than one box, preferrably more than two.
This requires some more involved synchronization and locking on top of the
cache invalidation.  And make sure that the multi-'rw' cluster stays alive
if one of the participants freezes and doesn't respond anymore.

Scrolling through the UFS/FFS code I think the first one is 2-3 days of
work.  The second 2-4 weeks and the third 2-3 month to get it right.
If someone would throw up the money...

-- 
Andre