[linux-lvm] Re: (reiserfs) Re: AIX JFS dual-mount

[Tracy R Reed]

On Fri, Jan 28, 2000 at 05:47:01AM -0800, Chris Mason wrote:
> On Fri, 28 Jan 2000, Russell Coker wrote:
> > A colleague told me that with AIX machines you can have two systems mount the
> > same file system, they then lock the bus whenever they need to do updates.
> > 
> > Can this give usable write performance?  If so is it worth considering?
> > 
> Only if you also include some kind of lock manager.  Without it, the two
> boxes would have no way if knowing if and when their caches are still
> valid.  
> 
> Once you have the lock manager, you don't need the full device 
> lock, the systems can coordinate who is writing/reading which blocks.
> 
> Anybody know exactly what AIX provides here?  

Sounds similar to GFS (which I only recently learned about and find totally
amazing and plan to play with soon and perhaps implement it in a production
environment if it is all it's cracked up to be) only not over fibrechannel. It
does fine grain locking, manages cache coherency, the works:

www.globalfilesystem.org

I've been meaning to mention this to you guys and make sure everyone was aware
of it. It is a journalling filesystem while allows multiple hosts to mount the
same filesystem at the same time. I hope to see a lot of integration between
reiserfs, GFS, LVM, and MD in the future. There is currently a lot of overlap
in these areas. Linux needs all of these features to be smoothly integrated
and very stable if it is going to go head to head with the big boys someday.

--
Tracy Reed      http://www.ultraviolet.org