AIOps

AIOps

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  • 1.  Understanding HTTP session management and how it works

    Posted Mon July 29, 2013 08:43 AM

    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.


    www.ibm.com/developerworks/websphere/tec...


    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.



  • 2.  Understanding HTTP session management and how it works

    Posted Mon July 29, 2013 03:12 PM
    Mihir,

    Without WXS if the in-memory session pool is full then the LRU session would be removed and gone forever. To mitigate this your options are to increase the in-memory pool size or define a persistent data store.  If you choose to increase the in-memory size then your JVM heap usage increases, if you choose Memory to Memory session replication then you have additional overhead on the Application Servers to replicate that data.

    Once WXS is implemented it takes over all session management functions which reduces total overhead along with a significant number of other benefits.

    I would recommend reading through this redbook, specifically chapter six for the most current information on WXS.

    publib-b.boulder.ibm.com/redpieces/abstr...

    Thanks,
    Drew


  • 3.  Understanding HTTP session management and how it works

    Posted Mon February 24, 2014 06:58 AM
    hi

    how can i test and check and monitor all session in cluster nodes?

    i want monitor session replication  in some node to other node

    note: i have 1 dmr 4 ihs 5 nodes