Tuning the dynamic cache provider

The WebSphere® eXtreme Scale dynamic cache provider supports the following configuration parameters for performance tuning.

About this task

  • com.ibm.websphere.xs.dynacache.ignore_value_in_change_event: When you register a change event listener with the dynamic cache provider and generate a ChangeEvent instance, there is overhead associated with deserializing the cache entry so the value can be put inside the ChangeEvent. Setting this optional parameter on the cache instance to true skips the deserialization of the cache entry when generating ChangeEvents. The value returned is either null for a remove operation or a byte array containing the serialized form of the object. InvalidationEvent instances carry a similar performance penalty, which you can avoid by setting com.ibm.ws.cache.CacheConfig.ignoreValueInInvalidationEvent to true.
  • com.ibm.websphere.xs.dynacache.enable_compression: By default, the eXtreme Scale dynamic cache provider compresses the cache entries in memory to increase cache density, which can save a significant amount of memory for applications like servlet caching. If you know that most of your cache data is not be compressible, consider setting this value to false.