International Business Machines Corporation

Donald Ray Stence

Stephen Bailey Peckham

Khalid Filali-Adib

John Mark McConaughy

David W Sheffield

Frederic Barrat

Marc Joel Stephenson

Sungjin Yook

Philippe Bergheaud

Laurent Dufour

Luke Mathew Browning

Christophe Lombard

Guy Menanteau

Brian William Thompto

Wen-Tzer Thomas Chen, Jr

Diane Garza Flemming

Mysore Sathyanaranyana Srinivas

William A Maron

Basu Vaidyanathan

Mohit Karve

John Barry Griswell, Jr

Calvin Lui Sze

Sandy K Kao

Norman Edward Brake, Jr

A set of dependence relationships in a set of program instructions is detected by a processor. The set of dependence relationships comprises a first load instruction to load a first data object and a second load instruction to load a second data object from a second address that is provided by address data within the first data object. The processor identifies a number of dependence instances in the set of dependence relationships and determines that the number is over a pattern threshold. The processor sends an enhanced load request to a memory controller. The enhanced load request comprises instructions to load the first data object from a first address on a physical page, locate address data in the first data object based on a memory offset, load the second data object from a second address in the address data, and transmit the first and second data objects to the processor.

Prefetching workloads with dependent pointers

A system and method adjust instruction dispatch in a multi-pipeline processor core having a plurality of execution units for improved performance of out-of-order execution of instructions. A dispatch adjust circuit receives a queue full signal from one or more of the execution queues that indicates the corresponding execution queue is full. In response to the queue full signal, the instruction dispatch circuit sends a stop signal to the instruction issuer to stop issuing additional instructions to the queues until one or more of the queues are empty. The dispatch adjust circuit may also receive a queue empty signal from the queues to detect when they are empty to send a start signal to the issuer.

Starting and stopping instruction dispatch to execution unit queues in a multi-pipeline processor

Mechanisms are provided for performing a live update of an operating system. The mechanisms receive an update to an operating system and clone a root volume group associated with an operating system instance executing in a first logical partition of the data processing system to generate a cloned root volume group. The mechanisms apply the update to the cloned root volume group to generate an updated and cloned root volume group and boot a second logical partition of the data processing system using the updated and cloned root volume group. Moreover, the mechanisms migrate application instances and application data to the second logical partition.

Live operating system update mechanisms

A symbol resolution unit can be configured for resolving conflicting operating system symbols. A default symbol resolution data structure can be accessed to resolve a symbol associated with a client of an operating system. A first data entry that corresponds to the symbol is located in the default symbol resolution data structure. It is determined that the first data entry indicates that the symbol is marked special (e.g., as a conflicting operating system symbol). A secondary symbol resolution data structure is accessed in response to determining that the first data entry indicates that the symbol is marked special. A second data entry that corresponds to the symbol is located in the secondary symbol resolution data structure based, at least in part, on an identifier of the client. A memory location indicated in the second data entry that corresponds to the symbol is provided to the client.

Minimizing overhead in resolving operating system symbols

A kernel extension associated with a first instance of an operating system can be detected. The kernel extension is configured to extend functionality of the kernel when loaded in a kernel managed by a second instance of the operating system. Some embodiments are further directed to detecting symbols for the kernel extension, where the symbols specify one or more functions associated with the kernel extension. Some embodiments are further directed to generating a first namespace that is assigned only to the first of the plurality of instances of the operating system. The first namespace is separate from a second namespace for the second of the plurality of the instances of the operating system. Some embodiments are further directed to storing the symbols in the first namespace.

Controlling kernel symbol visibility and accessibility across operating system linkage spaces

A method and a computer program product that enable an existing operating system (OS) to provide a non-failure response to an application's reference to an OS service that is not currently defined/available within the existing OS. The loader of the OS responds to each reference to an undefined service by mapping the reference to an undefined service response utility (USRU). USRU is a specialized service designed to provide a response that a requested service is not yet available. When the OS loader detects that an application is referring to an OS service that is undefined, the OS loader resolves the reference to the USRU, which, when invoked returns an indication that the requested service is not yet available.

Method and computer program product for handling application references to undefined operating system services

Growing community of inventors

Pflugerville, TX, United States of America

Donald Ray Stence