I can't use SimpleTcpCluster because I am not permitted to use multicast
on our network.

Gary

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of
Yoav Shapira
Sent: Monday, January 16, 2006 2:34 PM
To: Tomcat Developers List
Subject: Re: Extending PersistentValve ?

Hi,
I don't have much to comment besides what you already pointed out:
this approach would suffer a performance penalty on each and every
request, and (on a decently configured network) would end up slower than
the SimpleTcpCluster multicast solution.  Why can't you use the latter?

Before you reply: now that you've solved your ClassCastException, this
becomes more of a user issue, so please take the discussion to
users@tomcat.apache.org rather than [EMAIL PROTECTED]  Thanks,

Yoav

On 1/16/06, Gary Blomquist <[EMAIL PROTECTED]> wrote:
>
> The ClassCastException fixed.  I had the valve configured incorreclty 
> in the server.xml.
>
> Would still appreciate feedback on the approach discussed below.
>
> Thanks,
>
> Gary
>
> -----Original Message-----
> From: Gary Blomquist [mailto:[EMAIL PROTECTED]
> Sent: Monday, January 16, 2006 2:12 PM
> To: Tomcat Developers List
> Subject: Extending PersistentValve ?
>
> I would like to be able to use round robin loading balancing with a 
> JDBCStore.  However, it appears that using the PersistentManager with 
> JDBC store could cause the sessions to be stale when a session 
> migrates between workers due to the asyncronous behavior of the 
> PersistentManager.  (I realize their is a SimpleTcpCluster available 
> as a clusterering solution but I can not use because it relies on
> multicast.)
>
> Viewing the source it appears that the PersistentValve with the
> PersistentManager  and JDBCStore could be a solution.   It appears
that
> it would load a session from the store at the begging of each request 
> and save it back to the store at the end of the request.  I would like

> to modify the behavior to only load/save when the session is dirty 
> based on the last_access timestamps.
>
> Any comments on the solution? ( I realize their is some performance 
> penalty due to object serialization and writing blobs to the database;

> however, in our case I think this would not be prohibitive esp. if 
> there is a small amount of data in the session.)
>
> Also,  when I attempt to run Tomcat with the PersistentValve I get the

> following exception:
>
> SEVERE: An exception or error occurred in the container during the 
> request processing
> java.lang.ClassCastException: org.apache.catalina.core.StandardEngine
>         at
> org.apache.catalina.valves.PersistentValve.invoke(PersistentValve.java
> :9
> 9)
>         at
> org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java
> :1
> 48)
>         at
> org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199)
>         at
> org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282)
>         at
> org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:744)
>         at
>
org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:
> 674)
>         at
>
org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.
> java:866)
>         at
> org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPo
> ol
> .java:684)
>         at java.lang.Thread.run(Thread.java:595)
>
> Note:  (I have not yet made mods to the PersistentValue)
>
>
> Thanks for your assistance,
>
> Gary Blomquist
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED] For 
> additional commands, e-mail: [EMAIL PROTECTED]
>
>


--
Yoav Shapira
System Design and Management Fellow
MIT Sloan School of Management
Cambridge, MA, USA
[EMAIL PROTECTED] / www.yoavshapira.com

---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED] For additional
commands, e-mail: [EMAIL PROTECTED]


---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to