Topic
  • 2 replies
  • Latest Post - ‏2014-10-10T18:07:11Z by rickchen@ca.ibm.com
smart_dev
smart_dev
56 Posts

Pinned topic Understanding HTTP session management and how it works

‏2013-07-15T14:23:09Z |

Hi,

 

Recently, I was involved into WebSphere Portal session management with WXS(stand-alone). I was going through the following article on IBM site and bit surprise to know that WXS just replicates/copies session from WebSphere portal JVM to WXS grid. I was thinking that local JVM doesn't store any session object after offloading it to WXS grid. But I guess I was wrong.

Here is a stanza which clarifies this.

"After HTTP session management is initiated, WebSphere eXtreme Scale replicates every new session created on WebSphere Application Server into the grid container, once for every predefined session replication interval. The WebSphere eXtreme Scale container is located on another server instance where all of the other cluster members can share and obtain the session data. Should an application server go down, the other application servers can still obtain the latest session data to implement HTTP session failover.

In the case where the WebSphere Application Server in-memory session count reaches its maximum size, WebSphere eXtreme Scale removes the least recently used session to make room for the new one - but it does not remove the session replica. Even if WebSphere Application Server is not able to find the actual data for that session, it still can retrieve the replica from WebSphere eXtreme Scale."

You can find below URL for the document.

http://www.ibm.com/developerworks/websphere/techjournal/1301_ying/1301_ying.html

If this is the way it is implemented then how would the local JVM heap be freed to improve the performance of the application? 

Any thoughts on this will be appreciable.

Thanks.

  • smart_dev
    smart_dev
    56 Posts

    Re: Understanding HTTP session management and how it works

    ‏2013-07-18T07:36:32Z  

    Can someone answer my query and confirm my understanding?

    Appreciate!!

  • rickchen@ca.ibm.com
    rickchen@ca.ibm.com
    3 Posts

    Re: Understanding HTTP session management and how it works

    ‏2014-10-10T18:07:11Z  
    • smart_dev
    • ‏2013-07-18T07:36:32Z

    Can someone answer my query and confirm my understanding?

    Appreciate!!

    the splicer property sessionTableSize can configure the amount of sessions to store in the in-memory cache.