Re: [Gluster-devel] RPM / BerkeleyDB on GlusterFS

[Brent A Nelson]

On Mon, 12 Jan 2009, Gordan Bobic wrote:

> Brent A Nelson wrote:
> > I believe you're looking for shared writable mmap support, which requires a 
> > very recent (maybe) or painfully-patched FUSE; it's not really up to 
> > GlusterFS (I think it will probably just work, if your FUSE is somehow able 
> > to support it).
>
> I was actually more thinking about an option to rpm/bdb to make it no use 
> mmap.

I don't know for rpm; apt-get certainly did not have any such option, 
although someone did create a patch to disable it in apt-get.

> > So, if you can't get shared writable mmap to work, try the workaround with 
> > tmpfs or another filesystem (perhaps even an NFS mount of a GlusterFS 
> > directory).
>
> Would that actually work? Exporting /var/lib/rpm via NFS and mounting it to 
> fake some kind of mmap support? It's an inspired solution, I'll grant you 
> that. I'll have to try it. :-)

tmpfs certainly worked in my case, and others claimed that NFS in general 
would work.  NFS to a filesystem that doesn't itself support shared 
writable mmap (such as GlusterFS or any other FUSE filesystem)? Well, we 
probably won't know for sure until you try it. ;-)

Check with tmpfs first, to make sure you've set up any necessary symlinks 
(as tmpfs certainly should work), and then try switching to GlusterFS NFS 
re-export.

Thanks,

Brent