International Business Machines Corporation

Jonathan Allen Wildstrom

Bruce Gerard Mealey

Thomas Stanley Mathews

Oliver Dial

Matthew David Fleming

Michael E Lyons

Priti Ashvin Shah

Systems, computer-implemented methods, and computer program products to facilitate approximating a range of sideband frequencies efficiently are provided. According to an embodiment, a system can comprise a processor that executes computer executable components stored in memory. The computer executable components comprise a wave division component that generates a plurality of waveform snippets using a definition of an intended waveform, wherein the plurality of waveform snippets can be phase shifted. The computer executable components further comprise rotation component that assigns a phase rotation to be applied to at least one waveform snippet of the plurality of waveform snippets, wherein the phase rotation is out of phase with a previous waveform snippet of the plurality of waveform snippets.

Approximation of a range of sideband frequencies efficiently

Techniques regarding error detection in one or more generated signals based on one or more signal-to-noise ratios are provided. For example, one or more embodiments described herein can include a system, which can include a memory that can store computer executable components. The system can also include a processor, operably coupled to the memory, and that can execute the computer executable components stored in the memory. The computer executable components can include a signal analysis component that can determine a signal-to-noise ratio associated with a generated signal, wherein the signal-to-noise ratio incorporates a signal value based on a reference signal and a noise value based on a difference between the reference signal and an acquired signal.

Signal-to-noise based error detection

A method, computer program product, and data processing system for preventing the occurrence of undetectable dangling pointers through memory reallocation are disclosed. Allocated memory regions that are no longer needed are deallocated but are not immediately freed for reallocation, being designated as 'retained.' A memory retention metric is computed as a measure of an extent of the retained memory regions in the computer's memory space. Once the memory retention metric exceeds a pre-determined threshold, some or all of the retained memory regions are freed for reuse. In this manner, improper accesses to deallocated memory regions can be detected more easily, since reuse of those regions is delayed, while at the same time excessive resource usage and heap fragmentation is avoided by only retaining deallocated regions for a limited time (determined by the threshold and retention metric chosen).

Detecting illegal reuse of memory with low resource impact

Methods, apparatus and computer program products for removal of elements from a linked list while other elements of the linked list are allowed to be accessed during the removal operation. In one embodiment, the method, apparatus and computer program product include identifying an add/remove area of a linked list and a static area of the linked list. Elements may only be added or removed from the linked list in the add/remove area or by a garbage collector that performs garbage collection only on elements in the static area of the linked list. The garbage collector identifies an element after the last element in the add/remove area and performs garbage collection beginning with that element and moving through the static area. In an alternative embodiment, a 'next element' pointer in a previous list element is set to point to the element being deleted's 'next element' pointer. Any global references to the element being deleted must be modified. A message may then be issued to the processors of a multiprocessor system at a same interrupt priority as a reading process priority. Once the processors respond to the message, garbage collection may be performed on the element to be deleted.

Apparatus and method for removing elements from a linked list

The present invention provides an apparatus, method and computer program product for privatizing operating system data. With the apparatus, method and computer program product of the present invention, a block of memory is allocated and divided into identical, smaller, properly aligned storage areas, each dedicated to a single processor in a multiprocessor system. The storage areas are allocated either initially when the system is initialized or on an as needed basis. Each sub-allocation request is made to use storage at the same location relative to the start of that processor's storage space. Because each processor's storage is isomorphic to all other processors, only one allocation record for all processors is needed, thereby reducing the overhead of the data privatization scheme. By allocating memory in this manner, cache line contention is minimized.

Growing community of inventors

Austin, TX, United States of America

Jonathan Allen Wildstrom