On Wed, Feb 13, 2008 at 07:34:20PM -0500, Jim Fulton wrote: > > On Feb 13, 2008, at 6:14 PM, Binger David wrote: > >> >> On Feb 13, 2008, at 3:58 PM, Jim Fulton wrote: >> >>> Note that, IMO, some of the best use cases for multi databases are >>> separating catalog and session data from regular content. >> >> Could you say more about what the benefit of this separation is, > > Catalogs and session data change much faster than content. It makes sense > to pack these more frequently. On large system, it provides the ability to > spread load over multiple servers, if necessary.
Also, as I understand it, you can get more benefits from the "regular content" ZODB cache if you're not constantly moving tons of catalog data through it, so there's a performance win. We've been discussing doing this for openplans.org... one question that came up that none of us knew the answer to: If I undo some changes to content, what happens to the index values for that content? Does undo fire an ObjectModifiedEvent? If not I'd guess that the catalog will still contain pre-undo data. -- Paul Winkler http://www.slinkp.com _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
