Abstract: A processor-implemented method manages a data cache for a computer system. One or more processors maintain a cache for one or more data resources requested by a client process. In response to a request from the client process for a cached data resource, the processors send a first request to a server process for the data resource, and a second request to the server process for an indication of whether or not the data resource has been modified since the data source was most recently cached. Responses to the first or second requests from the server process are compared with the cached data resources so as to identify whether the response to the second request is inaccurate. One or more processors disable caching for the data resource in response to a predetermined number of inaccurate second requests associated with the data resource being identified.

Abstract: A processor-implemented method manages a data cache for a computer system. One or more processors maintain a cache for one or more data resources requested by a client process. In response to a request from the client process for a cached data resource, the processors send a first request to a server process for the data resource, and a second request to the server process for an indication of whether or not the data resource has been modified since the data source was most recently cached. Responses to the first or second requests from the server process are compared with the cached data resources so as to identify whether the response to the second request is inaccurate. One or more processors disable caching for the data resource in response to a predetermined number of inaccurate second requests associated with the data resource being identified.

Abstract: A method and system for increasing a system's performance and achieving improved memory utilization by approximating the memory sizes that will be required for data objects that can be deserialized and constructed in a memory cache. The method and system may use accurate calculations or measurements of similar objects to calibrate the approximate memory sizes.

Abstract: A method and system for increasing a system's performance and achieving improved memory utilization by approximating the memory sizes that will be required for data objects that can be deserialized and constructed in a memory cache. The method and system may use accurate calculations or measurements of similar objects to calibrate the approximate memory sizes.

Abstract: A computer system includes a virtual machine supporting an object-oriented environment, in which programs to run on the virtual machine are formed from classes including methods. Applications run on the virtual machine. After a first such application has run on the virtual machine, a reset is performed on the virtual machine. The reset calls a first method in a class to perform a tidy-up operation which effectively puts the virtual machine back into a clean state. Subsequently a second application can be started on the virtual machine. As part of this start-up, the system calls a second method in the class to perform a reinitialization of the class.

Abstract: A system includes first and second virtual machines (VM) representing a master and a client respectively. A class file is loading by the first virtual machine into shared memory. The class file includes sharable and non-sharable data, and also references sharable and non-sharable data (including code). When it is desired to load the same class into the second virtual machine, the class is first located within said shared memory. A mirror copy of the class is then formed within private memory in the second virtual machine. Finally the non-sharable data of the class is completed in the private memory. Thereafter, an application in the second virtual machine can utilise the class on the basis of the sharable data in the shared memory of the first virtual machine, and the non-sharable data from the private memory of the second virtual machine.