Updated JSPs are not picked by are not picked up by all clones

Technote (FAQ)
Problem
In a WebSphere® Application Server 3.5.X cloned environment, a JSP™ is updated and the update is not picked up by all clones. The first clone that serves a request after the JSP has been updated causes the JSP to be recompiled; however, the other clones in the environment do not pick up the change.
Cause
Each clone shares the same temp directory. The first clone that serves the request after the JSP is updated causes the recompile to occur; as a result, the first clone has the updated JSP. However, the other two clones do not have the updated JSP.

This is because the *.class and *.dat files are kept in memory of each clone. The jsp processor compares the timestamp of the JSP to the timestamp of the *.class file in the temp directory, sees that it does not need recompiling, and uses the old copy.

Although updating a JSP without stopping and restarting the clones is not recommended, there is a workaround to this problem.

Solution
Starting with WebSphere Application Server 3.5.5, a JVM system property called com.ibm.clone.separate.temp.target.dirs was introduced. Setting this to true causes each clone to have their own temp directory. This results in each clone getting the updated JSP. To enable this feature, set up the following:
  1. Create a file named global.properties in the WAS_INSTALL_ROOT/properties/ directory.

  2. Add the following line to the global.properties file: com.ibm.clone.separate.temp.target.dirs=true

  3. Stop and restart the Administrative Server.

This is documented in the release notes for 3.5.5 located at : http://www-3.ibm.com/software/webservers/appserv/doc/v35/ae/infocenter/was/relnotes_fp5.html
Cross Reference information
SegmentProductComponentPlatformVersionEdition
Portals - Commerce - PersonalizationWebSphere Portal for MultiplatformsGeneralPlatform Independent2.1, 2.1.4All











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, Servlet Engine/Web Container
Operating system(s): Multi-Platform
Software version: 3.5
Software edition: Advanced, Enterprise
Reference #: 1113187
IBM Group: Software Group
Modified date: 2004-05-17