[ale] XFS multi-mount

[Jeff Hubbs]

If you're hell-bent on doing such a thing, this may be one of those
cases where Linux just ain't your OS (don't feel bad - I say that of
Windows a whole lot more).

VMS will do it, but I'd have to leave it up to you to find out what your
hardware platform future is (you may not have one).  The corner that VMS
shops are painted into gets a little bit smaller every day.

Jeff

On Mon, 2004-12-20 at 17:05, Greg Freemyer wrote:
> Attriel,
> 
> I assume you know that what you are doing is simply not supported by
> most filesystems, right?
> 
> The "correct" thing to do would be to try a cluster filesystem. 
> 
> For what you describe, I think GFS from Redhat or OCFS from Oracle
> would be the best GPL choices.  Both are designed  to have multiple
> nodes accessing a common shared storage array.
> 
> Unfortunately neither of these is likely to be as fast as XFS.  
> 
> I would check out OCFS first.  It has some short-comings (no locking,
> no acls, etc.),  but I don't think you need those features.
> 
> If you need XFS, you could also try mounting with the sync flag.  That
> tells xfs to keep the servers write buffer flushed to disk at all
> times.  Unfortunately, the sync flag really slows down XFS's
> performance.
> 
> That would fix your write caching issues.
> 
> As Dow said, it is your read cache that is likely the real difficulty.
>  Maybe you could post on the XFS list and someone could tell you of
> way to invalidate all the read cache pages, thus forcing a physical
> read.  If that could be done every 30 seconds or so, it might work for
> you.
> 
> Greg