Autonomically adjusting one or more computer program configuration settings when resources in a logical partition change

An apparatus comprising:

• at least one processor;
• a memory coupled to the at least one processor;
• a plurality of logical partitions defined on the apparatus;
• a dynamic partition manager residing in the memory and executed by the at least one processor, the dynamic partition manager determining an allocation of hardware resources among the plurality of logical partitions and having an ability to dynamically change the allocation of hardware resources while the logical partitions are running;
• and
• an application server residing in the memory and executed by the at least one processor, the application server including a configuration setting for threadpool size, a configuration setting for heap side, a configuration setting for size of at least one buffer, and a configuration setting for cache size;
• the dynamic partition manager determining that a dynamic reallocation of hardware resources in the logical partition is needed;
• the dynamic partition manager sending a message to the application server regarding the dynamic reallocation of hardware resources in the logical partition before the dynamic partition manager makes the dynamic change to the allocation of hardware resources in the one logical partition;
• in response to receiving the message from the dynamic partition manager, the application server autonomically changing at least one of threadpool size, heap side, size of at least one buffer, and cache size in the application server, then responding with a message to the dynamic partition manager;
• the application server collecting performance statistics for the one logical partition;
• the application server comparing the performance statistics to at least one specified criterion to determine whether or not the application server will autonomically change the at least one configuration setting;
• if the dynamic change to the allocation of hardware resources increases a number of processors in the one logical partition, the application server increases the threadpool size and the heap size;
• if the dynamic change to the allocation of hardware resources increases memory size in the one logical partition, the application server increases the heap size and the cache size;
• if the dynamic change to the allocation of hardware resources decreases the number of processors in the one logical partition, the application server decreases the threadpool size and the heap size;
• and
• if the dynamic change to the allocation of hardware resources decreases the memory size in the one logical partition, the application server decreases the heap size and the cache size.