Hi, I'm writing a program to process some commands from an external party. Those commands act against some phone numbers. One actor is used to read the commands from files line-by-line. Then it issues the commands one by one (in Akka messages) to another actor. That actor will perform a series of operations according to the command it receives. The operations involves calling some external SOAP APIs and checking/updating some states in the program. I'm using separate actors to handle different SOAP APIs. Up to now, everything seems clear to me. Then the problem is, I need to maintain a large state in the program in the format of HashMap<String, MyData>, where MyData is a POJO containing a few fields, and the size of the map could be as large as 1 million. So I'm wondering how I should keep such a large state in Akka while allowing simultaneous insert/delete of records by other actors. It mostly won't perform well if I copy the whole object. What is the recommended way of doing such kind of thing? I'm thinking, if I use an embedded in-memory key-value store, and allow my actor to access it, I can let the IMDB handle the concurrency stuff and let multiple instances of the actor to access the data. However, does Akka have some easier ways to do it? Any suggestion is highly appreciated. Thanks!
Kane On 3 Mar, 2014, at 6:59 PM, √iktor Ҡlang wrote: > Any decent immutable collection does structual sharing. > > What's your access-pattern like? > > > On Mon, Mar 3, 2014 at 11:20 AM, Kane Lai <[email protected]> wrote: > However, won't it be slow if we are to copy a large object (e.g. HashMap)? > What's the recommended way to handle such kind of large state using Akka? > Akka Agent? STM? or I am even thinking using a separate embedded in-memory > DB, but seems it's overkilled... > I've searched lots of places in the internet but seems nothing is found... > > > On Saturday, June 30, 2012 3:47:06 AM UTC+8, Antony Stubbs wrote: > I suppose the other option is to create the copy when changing/setting > it's value, instead of when returning it. > > But what about model objects? Same thing I suppose. > > On 29 June 2012 14:57, Derek Williams <[email protected]> wrote: > > On Fri, Jun 29, 2012 at 11:55 AM, Antony Stubbs <[email protected]> > > wrote: > >> > >> What's the best practice for using Agents with collections like lists and > >> hashmaps? I.e. the complication being when you return the list, but adding > >> an item to the list can cause a concurrent modification exception. One > >> possibility is instead of returning the list, return a copy. But I don't > >> think Agent supports that as is? Same question I suppose for any type that > >> isn't a primitive - i.e. a model object like "User". > > > > > > The best practice is to avoid mutable collections or other mutable objects > > with Agents. You are probably using Java, so this might be more difficult > > since the use of mutable objects is much more common there. > > > > It might be possible for Akka to support a custom method for modifying the > > value before returning it? It's been a while since I've looked at the Agent > > code. > > > > -- > > Derek Williams > > > > -- > > You received this message because you are subscribed to the Google Groups > > "Akka User List" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]. > > For more options, visit this group at > > http://groups.google.com/group/akka-user?hl=en. > > -- > >>>>>>>>>> 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. > > > > -- > Cheers, > √ > > ——————— > Viktor Klang > Chief Architect - Typesafe > > Twitter: @viktorklang > > -- > >>>>>>>>>> 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 a topic in the Google > Groups "Akka User List" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/akka-user/klyQ-S60K18/unsubscribe. > To unsubscribe from this group and all its topics, 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. -- >>>>>>>>>> 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.
