Comments inline..
Orion Letizi wrote:
This is very cool. You beat me to it-- I was going to add a clustering
with geronimo to our wiki as well.
The more documentation the better. Feel free to use any of the content
from the Geronimo Wiki in your article. A few areas that could be
explored a bit more in depth include:
- Details on tc-config.xml and defining which application objects are
appropriate for inclusion in this file.
- Details on how to use a JVM other than the one installed with the
Session Configurator
- EJB Clustering details (when the support is fully available)
At the end of the page, you list a few open questions:
Investigate if there is a slimmed down Terracotta sessions download
image that doesn't include the Session Configurator, JDK, samples, etc
Investigate if there is a slimmed down Terracotta sessions download
image that doesn't includes only the Terracotta Client.
Our next release will have only a single, monolithic kit. The current
Terracotta Sessions kit actually does include the server, it's just
packaged up a bit differently. The multiple kits were very confusing to
people, so we decided to collapse them all (DSO, Spring, and Sessions)
into a single kit. As for a reduced kit that doesn't include
configurator, jdk, samples, etc.-- I'll cross-post this to tc-dev and
bring the subject up there.
Seems that the Terracotta Installer could make the non-production stuff
(Session Configurator, Samples, JDK, etc.) optionally selectable during
the install process. Also it may be interesting to consider separate
installation options for Terracotta Server and Terracotta Client (if
this provides any significant disk space savings).
Investigate if Open Terracotta plans to support the Jetty Web Container.
Jetty support is currently in the works. I personally really like Jetty.
Will add this to the FAQ. Please post back here when this available.
Investigate Sticky Session support.
Not sure what you mean by this...
Tomcat and Mod-jk provide the ability to have the load balancer lock a
particular httpsession (identified by session cookie) to a specific
cluster member. This cluster member will serve all the requests for
this session until the cluster member tops/fails and failover to a new
cluster member occurs. This "stickiness" is quite useful for the case
of multi-frame JSPs where it is important that all concurrent requests
are executing in the same JVM (as per Java EE specifications). Hmmm,
now that Terracotta provides the concept of a global cross-node JVM, I'm
wondering how important this is now .. though still seems there would be
performance overhead in locking across JVMs.. so I think Sticky
Session is still useful..
Anyway, I suspect the following two snippets are involved though haven't
gotten them to work with Geronimo and Terracotta yet..
<gbean name="TomcatEngine">
<attribute name="initParams">name=Geronimo jvmRoute=nodeXYZ</attribute>
</gbean>
<reference name="Valve1">
<pattern>
<groupId>geronimo</groupId>
<artifactId>tomcat</artifactId>
<version>1.1.1</version>
<type>car</type>
<name>JvmRouteBinderValve</name>
</pattern>
</reference>
Any thoughts?? Jeff?? Filip??
Investigate when Open Terracotta will support EJB clustering for
Geronimo.
EJB clustering is also in the works. Tim Eck (one of our developers)
and Jeff Genender were working on EJB clustering a couple of weeks ago.
They got prototype EJB clustering working. Not sure of the current status.
Ok, will check with Tim and Jeff..
Thanks
-Dave-
Investigate when Open Terracotta will support the IBM JDK.
We're planning on doing IBM JDK support soon, although I'm not sure if
it's been slated for a specific release yet. My guess is sometime in
the first half of this year-- but, that's just a guess.
Cheers,
Orion
I've added an article to the Geronimo wiki that describes how to cluster
Geronimo HTTP Session web application data using the Open Terracotta
project.
http://cwiki.apache.org/GMOxDEV/clustering-geronimo-with-open-terracotta.html
Feel free to get it a try..
