International Business Machines Corporation

Mike Stephen Fulton

Dan F Greiner

Charles W Gainey, Jr

Damian Leo Osisek

Mark S Farrell

Vijay Sundaresan

Mark Anthony Check

John Robert Ehrman

Mark Graham Stoodley

Ali Ijaz Sheikh

Peter Jeremy Relson

Graham Alan Chapman

Sean Christopher Foley

Derek Bruce Inglis

Nikola Grcevski

Ajith Ramanath

Kushal Sayeed Munir

Christopher B Larsson

Eric V Simpson

Kishor V Patil

David W Dykstal

Dave K McKnight

Rick L Sawyer

Anderson Klegues Fraga

Brian James Minchau

Robert Paul Duncan

Radhakrishnan Thangamuthu

A computer implemented method, a computer program product and a data processing system for executing an application written in a dynamic language are provided. An execution point of the application is loaded. A list of classes associated with the execution point is generated. The loading of each class in the list of classes is simulated. New execution points and new classes accessible from each execution point within each class in the list of classes are identified by recursively parsing instructions associated with each execution point. The list is modified to include the identified new execution points and new classes. Responsive to a determination that new execution points and new classes have been identified, the steps of identifying new execution points and new classes and modifying the list is repeated. The list is saved.

Conservative class preloading for real time Java execution

A method implemented by a processor and a system develop a software project targeting one or more remote systems. The method includes generating a project on a local system, which includes receiving user input through a user interface. The project includes one or more source files. The method also includes generating one or more remote contexts corresponding to the one or more remote systems.

Multi-context remote development

A computer-implemented process for creating a packed data object, the computer-implemented process comprising providing instrumentation to an enhanced runtime by an enhanced compiler for a computer executable program portion, detecting a special class in the computer executable program portion by the enhanced runtime, creating an internal representation of a packed data object header using the instrumentation, calculating a size of elements for a packed data object associated with the computer executable program portion, determining a type of packed data object using information in the packed data object header, and responsive to a determination that the type of packed data object is an on-heap packed data object, storing the packed data object header and associated packed data object data together for the packed data object in a memory heap.

Packed data objects

Embodiments of the present invention provide a method, system and computer program product for dynamic feasibility analysis of event-driven program code. In an embodiment of the invention, a method for a dynamic feasibility analysis of event-driven program code can be provided. The method can include loading multiple different tasks associated with different registered events in event-driven program code of an event-driven application, reducing overlapping ones of the registered events for different ones of the tasks to a single task of the overlapping events to produce a reduced set of tasks and corresponding events, ordering the corresponding events of the reduced set of tasks and grouping the corresponding events by time slice for the event-driven application, and reporting whether or not adding a new event to a particular time slice for the event-driven application results in a depth of events in the particular time slice exceeding a capacity of the particular time slice rendering the event-driven application infeasible.

Dynamic scheduling feasibility analysis of event-driven applications based on reducing tasks of overlapping events

A method, computer program product, and data processing system for substituting a candidate instruction in application code being loaded during load time. Responsive to identifying the candidate instruction, a determination is made whether a hardware facility of the data processing system is present to execute the candidate instruction. If the hardware facility is absent from the data processing system, the candidate instruction is substituted with a second set of instructions.

Instruction exploitation through loader late fix-up

There is provided a computer implemented method for determining the efficiency of a runtime compiler. A set of execution times representing the time taken for program code to perform a set task after two or more runtime compilations is recorded. A first metric as the difference between the first execution time and the last execution time of the set of execution times, a second metric as the average throughput improvement from the set of execution times, and a third metric as the time taken for the compiler to achieve the maximum throughput from the set of execution times is calculated. Finally, an efficiency metric is calculated using the first, second and third metrics to determine the efficiency of the compiler.

Determining compiler efficiency

A computer implemented method, apparatus, and computer program product for copy-on-write optimization of immutable objects. An immutable object is marked as read-only to form a read-only object. The read-only object is formed to delay copying of the immutable object until a runtime determination is made that a write to the immutable object will be made. In response to an attempt to write to the read-only object, an internal value of the read-only object is copied to read-and-write storage using runtime information to form a writable copy of the read-only object. A set of references for the read-only object is updated to point to the writable copy of the read-only object. Delaying copying of the immutable object optimizes a copy-on-write of the immutable object.

Copy-on-write optimization of immutable objects for objects oriented languages

A computer implemented method, apparatus, and computer usable program product for system management. The process schedules a set of application tasks to form a schedule of tasks in response to receiving the set of application tasks from a registration module. The process then performs a feasibility analysis on the schedule of tasks to identify periods of decreased system activity. Thereafter, the process schedules a set of system management tasks during the periods of decreased system activity to form a prioritized schedule of tasks.

Managing system resources

Load time instruction substitution

A method is provided for recording a list of facilities available to a program executing on an information processing system. In such method a storage location and a length of data are defined for recording the list of facilities by a program being executed on the information processing system. An instruction is issued by the program for determining the available facilities and recording the list of available facilities in accordance with the defined storage location and data length. A processor executes the instruction to determine the available facilities and record the list of facilities in accordance with the defined storage location and defined data length. The recorded list of facilities can then be read by the first program.

Enhanced un-privileged computer instruction to store a facility list

A register-based instruction optimization is provided for facilitating efficient emulation of a target instruction stream. The optimization includes for at least one instruction in a frequently executed sequence of target instructions: confirming that at least one register is marked as a read-only register for the sequence; confirming that each register of the at least one register has been detected to have a constant value for the at least one instruction in multiple prior iterations of the executed sequence; and response thereto, optimizing the at least one instruction by replacing the at least one instruction with at least one immediate form instruction having at least one constant value encoded directly therein from the at least one register. The optimization results in an optimized sequence of target instructions, which when translated into a sequence of host instructions, is more efficiently executed by a host computing environment.

Register-based instruction optimization for facilitating efficient emulation of an instruction stream

A system and method for reorganizing source code using frequency based instruction loop replication are provided. Code is reorganized based on the frequency of execution of blocks of the code so as to favor frequently executed blocks of code over rarely executed code with regard to subsequent optimizations. Frequently executed blocks of instructions are maintained within loop/switch statements and rarely executed blocks of instructions are removed from the loop/switch statements. The rarely executed blocks of instructions may be replicated after the loop/switch statement with a reference back to the loop/switch statement. In this way, when subsequent loop/switch statement optimizations are applied, the frequently executed blocks of instructions within the loop are more likely to benefit from such optimizations since the negative influence of the rarely executed blocks of instructions has been removed.

System and method for frequency based loop reorganization

In present computing systems having dynamic linked libraries (DLLs), the user must either explicitly provide directives at the source level or use linker and loader support provided by the computing system. The present invention enables an application programmer to use unmodified source code in conjunction with a compiler, prelinker and runtime library to develop and use DLLs. A DLL can be extended by adding new functions and variables without requiring users of the DLL to recompile or relink their application.

Growing community of inventors

Maple Ridge, Canada

Mike Stephen Fulton