This week's book giveaway is in the General Computing forum. We're giving away four copies of Arduino in Action and have Martin Evans, Joshua Noble, and Jordan Hochenbaum on-line! See this thread for details.
In Weblogic 8.1 server, at which point of time does session replication actually take place.For instance, suppose there are 3 servers in a group(across systems), and requests from a particular client go to server1.What i understand from clustering is that the session gets replicated to server2 and server3 - when actually does it take place? Is it during each request - if so wont there be an unnecessary overhead? Or is it during failure of server1 - in which case, how come the session in server1 gets replicated after server1 fails?
In a cluster env, replication happens when a value is bound or unbound from the Session/ServletContext objects. This happens every time, when an object is bound or unbound, and yes this could be a performance issue, considering that the amount of data that is stored in the Session/ServletContext objects.
Further, I am pretty sure that WebLogic follows a primary and secondary modeal for session replication so the session is not replicated to _both_ server2 and server3, just one of them.
<a href="http://www.tangosol.com" target="_blank" rel="nofollow">www.tangosol.com</a><br /><a href="http://www.tangosol.com/coherence.jsp" target="_blank" rel="nofollow">Coherence:</a> Easily share live data across a cluster!