Hi Richard, I saw that post of Martin's and even replied, as I'm very interested in this approach. One thing to keep in mind is that conceptually speaking the difference between durable and persistent is really not that huge. There is simply an assumption that something that's durable will eventually be disposed of, while something that is persistent will live forever. But how often is that later case really true?
Further, given that this approach to persistence is built on the event sourcing model and the idea is to be able to replay a sequence of events into the mailbox of an actor, this is really just an (heavily) enhanced version of a durable mailbox. I've read Jay Kreps and others talk about setting retention times on the order of weeks or months for Kafka topics, so really I don't see that there's a huge discrepancy here. You can even see some evidence of similar in this excellent post: http://radar.oreilly.com/2014/07/questioning-the-lambda-architecture.html. In the end, what we're talking about in both the persistent and durable cases are just long-term event logs -- the question is just what you consider long-term and which arbitrary time length you assign to the meaning of each. Personally, I'm excited about this possibility as it would allow reuse of an efficient storage mechanism for both event-sourced data and streamed event processing On Sat, Jul 12, 2014 at 6:35 AM, Richard Rodseth <[email protected]> wrote: > I saw a tweet from Martin Krasser that he was working on an Akka > Persistence journal plug-in for Kafka. This puzzled me a bit since Kafka > messages are "durable" rather than "persistent" - they are stored for a > configurable time. > > Could anyone comment on a typical usage? Assuming that your persistent > actor is going to get recovered before the Kafka topic expires seems odd. > > While the Akka/Kafka combination seems great, I always pictured it would > just involve ordinary actors playing the role of Kafka producers and > consumers. > > -- > >>>>>>>>>> Read the docs: http://akka.io/docs/ > >>>>>>>>>> Check the FAQ: > http://doc.akka.io/docs/akka/current/additional/faq.html > >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user > --- > You received this message because you are subscribed to the Google Groups > "Akka User List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/akka-user. > For more options, visit https://groups.google.com/d/optout. > -- Thomas Lockney [email protected] http://thomas.lockney.net -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
