On Google App Engine: Google App Engine is Available for Java now - It was released earlier this week. Check the link at http://code.google.com/appengine/docs/java/gettingstarted/
My Motivation to ask for SDB is because of my use cases. In my world - I have a constant stream of Preferences/Rating's flowing in asynchronously. As a result in my basic implementation of CF,before I got to Taste, I maintained a table for UserID to UserID Correlation score(Pearson and Euclidean) and ItemID to ItemID score - which were incrementally updated on each new Userid - Item Id - Rating transaction coming in. I liked this model because the model was getting updated behind the scene's constantly and for the consumer side(recommendations) I always had a userid to userid score available to me for immediate access. Given my usecase - I though that something like SDB would work fine because my results were already in database(and did not need to be calculated realtime) and I did not care about ACID properties for database. Would something like this work in TASTE. I have still not gotten an understanding of the implementation of Taste , but it seems that it calculates the userid to userid similarity realtime. Approaches like dumping the preferences to S3 and then updating via hadoop don't gel in with a Message Oriented Architectecture. I will send the error-log in the next email On Fri, Apr 10, 2009 at 2:34 PM, Sean Owen <[email protected]> wrote: > On Fri, Apr 10, 2009 at 10:24 PM, Niraj <[email protected]> > wrote: > > I am using vista and apparently some tests are failing for > > mvn install for CORE. > > That's probably it -- can you provide any errors? it is almost surely > something to do with paths, which I might be able to fix quickly. core > and examples must build for this to work. > > > > On another note: Has you out anythought to implementing TASTE for > a)google > > App Engine for Java and b) using simple db has the database > > App Engine is Python-only for the moment and no I would not seriously > consider reimplementing in Python myself. But it is to support Java > shortly. In that case, yes perhaps. > > I had already created a machine image (AMI) for Amazon's EC2 which > would load data from S3, process all recommendations, and shut down. > This sort of thing could be replicated on App Engine; it is a nice > model. > > However, even better, Amazon just announced an easy framework for > MapReduce (Hadoop) on EC2. On top of my to-do list is to put together > the steps to run recommenders this way. The Hadoop bindings are > already written; should be easy. This will be an even better model > that the App Engine / EC2 model above. So I suppose I'd focus on this > mostly. > > SimpleDB, Amazon's DB? I wouldn't object to a DataModel based on it. > My concern is that recommenders are so data-intensive and access data > so frequently that even a local database is quite slow -- let alone a > distributed database like SimpleDB. I sense it is not cut out for this > use case. >
