Using the cachesSharingPolicy parameter in WMM

Question

This technote discusses the cachesSharingPolicy parameter located in the /wmm/wmm.xml file.

Answer

After installing the latest Member Manager Cumulative fix, you can add the parameter, cachesSharingPolicy, in the wmm.xml file for the LDAP repository.

The valid cachesSharingPolicy values are:

• SHARED_PUSH (default)
• SHARED_PUSH_PULL
• NOT_SHARED

After getting the value, WebSphere Member Manager (WMM) sets the properties when initializing its caches.

In a WebSphere Portal cluster, remember to use the WMM check out/in process. See Managing the cluster (8: Manually editing Member Manager files on a federated node).

Example:

UUID="LDAP1"
profileRepositoryForGroups="LDAP1"
supportTransactions="false"
adminId="cn=root"
adminPassword="XXXXXXX"
cachesSharingPolicy="NOT_SHARED"

Cache instance names:

For the LDAP repository, there are 3 kinds of WMM caches:

• NamesCache
• GroupCache
• AttributesCache

The WMM cache instance name is formed by "Repository UUID" + "<xxx>Cache".

So changing the cachesSharingPolicy will change the replication type for example cache instances below:

• ws/LDAP1NamesCache
• ws/LDAP1GroupCache
• ws/LDAP1AttributesCache

Usage notes on how to select cache policy:

The NOT_SHARED option is useful when there is an affinity between a client and a web application server and the data is used only by that client (for example, a shopping cart).

The SHARED_PUSH option is useful when the entry is very heavily used by all clients (for example, a popular product display).

The SHARED_PUSH_PULL option is useful when the entry is shared by clients but is not accessed often enough to warrant pushing the entire cached object to all other servers (for example, a product display that is not popular).

Related information

Member Manager cumulative fix for WebSphere Portal 6.0