6.4.1 The Cache Monitor
The Cache Monitor is a fully supported dynamic cache management application that comes with WAS and can be installed from the WAS_HOME/installableApps directory.
The Cache Monitor application is the primary tool provided to allow administrators to manage the dynamic cache environment. It provides the following features:
- Cache statistics such as hit rates and cache size
- Displays the contents of the cache including cache keys and value dependencies
- Manual invalidation control over the cache contents
- Cache configuration details such as templates and dependencies
This tool is specific to the dynamic cache APIs and works regardless of whether you're using WebSphere eXtreme Scale or not. However the context of the values will be different if you are using WXS. When you are using the default dynamic cache provider, install the Cache Monitor application on each server to monitor to get statistics specific to that server. When you use WXS, the values refer to the WXS grid as a whole. With both approaches, these statistics are not synchronized and therefore can vary up to 10% for concurrent workloads.
At time of writing there is an issue that might cause deadlock on the WXS grid when trying to perform a full-cache clear. The problem is resolved in WXS V7.1.0.1. The resolution is also available as a patch.
When using WXS with the dynamic cache, consider using the technology preview called the Extended Cache Monitor. This is freely available from the developerWorks site at the following address:
The Extended Cache Monitor is an extension installed on top of the supplied Cache Monitor and works in the same way. The Extended Cache Monitor is better suited to managing multiple dynamic cache providers, such as the scenario we recommend here using WXS for web content and the default dynamic cache provider for data caches. It also provides a selection of MBean statistics and allows the viewing of object cache contents.
The Cache Monitor and Extended Cache Monitor are simple to set up and use, but if further information is needed, see the Information Center