[Mondrian] Catalog clustering

[Julian Hyde]

The simplest thing is to put the schemas in a web server. (Apache VFS generalizes this notion to other protocols… but HTTP is best IMHO.)

On Dec 4, 2014, at 11:32 AM, Luc Boudreau <lucboudreau at gmail.com> wrote:

> To refresh the schema cache, you would need to ping each node.
> 
> Roland has a good alternative, but the DSP is mondrian specific.
> 
> My personal favorite is to use a custom Apache VFS provider. You tell mondrian to fetch the schema from an arbitrary URL, something like "myschemas://schema_v1.xml". On the flip side, you create a VFS handler which serves the "myschemas://" protocol. The only change required for Mondrian is to enable UseContentChecksum=true in your connection URL. This way the contents of the XML virtual file is the cache key, not it's URL. 
> 
> The downside is that you start leaving behind a lot of stale schemas. They eventually will go away when the GC frees up that space, but it's important not to create millions and millions of different schemas with tiny differences. As much as possible, try to use the same schema structure and leverage role based security whenever possible.
> 
> On Thu, Dec 4, 2014 at 2:17 PM, Roland Bouman <roland.bouman at gmail.com> wrote:
> This may be way off. 
> 
> But since your database is shared already, could you make an implementation of the dynamic schema processor that reads the info for the schema from the database?
> 
> On Thu, Dec 4, 2014 at 8:11 PM, Hilario Fernandes <hilario.fernandes at cortex-intelligence.com> wrote:
> 
> Hi,
> 
> I'm working on an application that uses mondrian as it's Olap Server. The application can run several instances in a cluster environment sharing the same database.
> 
> The problem is that the cube structure might change trough one of the instances, leaving the others with an outdated schema.
> 
> Is there any kind o mechanism for storing the catalog that can be used to centralize it? Something similar to the cache, that can be implemented to our needs?
> 
> Any pointers here from the community?
> 
> Thanks
> 
> -- 
> Hilario Fernandes
> 
> _______________________________________________
> Mondrian mailing list
> Mondrian at pentaho.org
> http://lists.pentaho.org/mailman/listinfo/mondrian
> 
> 
> 
> 
> -- 
> Roland Bouman
> blog: http://rpbouman.blogspot.com/
> twitter: @rolandbouman
> linkedin: http://www.linkedin.com/profile/view?id=5142800&trk=tab_pro
> 
> Author of "Pentaho Solutions" (Wiley, ISBN: 978-0-470-48432-6 http://tinyurl.com/lvxa88) and "Pentaho Kettle Solutions" (Wiley, ISBN: 978-0-470-63517-9 http://tinyurl.com/33r7a8m)
> 
> _______________________________________________
> Mondrian mailing list
> Mondrian at pentaho.org
> http://lists.pentaho.org/mailman/listinfo/mondrian
> 
> 
> _______________________________________________
> Mondrian mailing list
> Mondrian at pentaho.org
> http://lists.pentaho.org/mailman/listinfo/mondrian

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.pentaho.org/pipermail/mondrian/attachments/20141204/d2219705/attachment-0001.html