Futures Trade Flow

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I thought that was a really great talk and really pleased I spent the hour watching it.

I have a question regarding transactions. In the system it shows trades entering the distributed cache via messaging e.g. point to point queue or topic which it subscribes to. It also says that persistence is via Hibernate mappings which are invoked asynchronously. I just wanted to get a feel for how the transactions work in this system e.g. in terms of trades entering the system does an initial persistence action take place, which has to succeed before the transactions with the queue or topic ends (so you don't lose the trade). When events are being executed against the domain objects and the data is changing, it's implied that async calls keep the persistence state synced with the cache state. How does the system ensure that writes aren't lost e.g. if the persistence is asynchronous how would you rollback the cache data if that action fails.

Thanks again.

Yes, I didn't expand on this area in the presentation. But within the transaction that takes the trade message off the topic, as well as the trade being saved to the cache it is also written to a file. The trades from the file are then persisted to the database via Hibernate asynchronously. Therefore the database call is out of the critical path, but the trade is persisted, initially to just a file.