Boorad's World

Joel Reymont has hacked Mnesia around a bit and added a new storage type.  In addition to 'ram_copies' and 'disc_copies' node types, Mnesia can now have Amazon S3 nodes (s3_copies).

He hacked the Mnesia internals pretty hard, but (from TFA):

I would say it was worth it, though, as I now can
- lock S3 buckets or "records" using {Bucket, Key}
- update several S3 records in a single transaction
- set up additional s3_copies replicas using mnesia:add_table_copy/3
- ensure that data is only written to S3 once
- have a large cluster of Yaws nodes use a small cluster of "master" Mnesia nodes with s3_copies replicas, thus keeping replication and transaction costs down.

I believe this was contract work, but I think the help he received from Ulf Wiger and others, plus the cruel and unusual punishment of announcing the results to us, is hopefully enough to compel him to release it as open-source at some point.  I am certainly interested.  Although I will admit that for a small- to mid-sized web app, Amazon EC2 and S3 are not too cost-effective just yet. 

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