Very interesting discussion, thanks for bringing it up, Michael! [more below]
26 feb 2014 kl. 16:47 skrev Martin Krasser <[email protected]>: > On 26.02.14 14:09, delasoul wrote: >> >>> But I really like the idea to also keep the view in memory when needed, >>> update it, shut it down when not used and bring it back easily by replaying >>> the corresponding processor or snapshotting the view. >> >> This is possible with all options 1-3 described above. >> >> The combination of an eventsourced processor and a view would be my >> preference, but as i said here I am struggling with the update policy. In >> certain use cases it will be completely sufficient to create and replay the >> view just on demand, but if keeping it in memory it has to get updated > > Depends on what inconsistency window your application is willing to accept. > You still can read any time from the view with eventual consistency > guarantees. Update(await = true) is only needed to achieve strong read > consistency. Furthermore, view updates are only incremental updates (not full > replays) so it may well be that in many cases they're not too expensive. > > A later useful extension to akka-persistence could be push-based views (in > addition to the current pull-based views). They are harder to implement as > they require distributed pub/sub that preserves message order. Yes, push-based views would indeed be a very natural extension of the current capabilities. I assume that it is most efficiently implemented with the help of the underlying journal, because otherwise it would just be a shim on top which maybe amortizes some of the polling cost by bundling calls together but which fundamentally is not “push”. Regards, Dr. Roland Kuhn Akka Tech Lead Typesafe – Reactive apps on the JVM. twitter: @rolandkuhn -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: http://akka.io/faq/ >>>>>>>>>> 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/groups/opt_out.
