We don't currently have any optimizations to provide "lightweight" session consistency (see #132), but if you do quorum reads + quorum writes then you are guaranteed to read the most recent write which should be fine for most apps.
On Tue, Sep 15, 2009 at 5:30 AM, Eric Bowman <[email protected]> wrote: > Mark Robson wrote: >> >> 2009/9/15 Matt Kydd <[email protected] <mailto:[email protected]>> >> >> We need to persist the sessions and associated shopping baskets / >> activity summaries somewhere and Cass seems like a good fit, without >> the restrictions imposed by SQL there would be less necessity to purge >> old sessions. >> >> >> Purging the old sessions in Cassandra would be nontrivial. Moreover, as >> Cassandra doesn't give you consistency, it's a very bad session store. >> >> Also seeing as session data are typically very small (If they're not, you >> have more problems), the motivation for storing them in Cassandra would be >> little. >> >> Why not use a conventional database with some redundancy solution - you'll >> get consistency and for the volumes of data that a web site - even a very >> busy one - has in its sessions, it won't be a problem. > > With regard to consistency, is it not possible with Cassandra to achieve > "Session consistency" as described here: > http://www.allthingsdistributed.com/2008/12/eventually_consistent.html > > Or, if not possible, not worth it? > > Thanks, > Eric > > > >
