2 Replies Latest reply on Jan 8, 2003 7:05 AM by jaksa

    SLSB replication algorythm

      Hi.
      I have some questions on how the SFSBs are replicated in JBoss. I have noticed that a SFSB state is broadcast after each invocation, is this right?
      Does the same happen inside transactions spanning multiple invocations, or is it broadcast only at the end of the transaction?
      And finally what is considered a SFSB state?
      TIA,

      Jaksa

        • 1. sFsb replication algorythm
          slaboure

          First of all, I guess you original title was wrong ;)

          Right now, I don't remember if the state is replicated at the end of the transaction or at the end of the call. I know that it has (still is?) been at the end of the invocation. I did wrote the code so that it is only replicated at the end of the transaction but don't remember if I have ever commited that...

          So, let's say the end of the transaction and the end of the call do match ;) If that's the case, then the state is replicated (using any protocol specified at the JG layer: tcp, multicast, broadcast, etc.) EXCEPT if you do implement a method having this signature on your bean implementation:

          public boolean isModified();

          If it exists, we will call it before propagating the state to other nodes. This is an easy to implement optimisation that comes from the CMP1.1-land.

          As for "what is a SFSB state", check the EJB spec wrt to State-Passivation: it is exactly the same definition that is used for clustering.

          Cheers,


          sacha

          • 2. Re: sFsb replication algorythm :)

            Thank you Sacha,

            Jaksa