International Business Machines Corporation

Jonathan Appavoo

Orran Yaakov Krieger

Paul Edward McKenney

Robert William Wisniewski

Dipankar Das Sarma

Dilma Menezes Da Silva

Marc Alan Auslander

Kevin Kin-Fai Hui

Andrew Arnott Baumann

A method, system and computer program product for managing requests for deferred updates to shared data elements while minimizing grace period detection overhead associated with determining whether pre-existing references to the data elements have been removed. Plural update requests that are eligible for grace period detection are buffered without performing grace period detection processing. One or more conditions that could warrant commencement of grace period detection processing are monitored while the update requests are buffered. If warranted by such a condition, grace period detection is performed relative to the update requests so that they can be processed. In this way, grace period detection overhead can be amortized over plural update requests while being sensitive to conditions warranting prompt grace period detection.

Read-copy update system and method

To dynamically update an operating system, a new factory object may have one or more new and/or updated object instances. A corresponding old factory object is then located and its version is checked for compatibility. A dynamic update procedure is then executed, which includes (a) changing a factory reference pointer within the operating system from the old factory object to the new factory object. For the case of updated object instances, (b) hot swapping each old object instance for its corresponding updated object instance, and (c) removing the old factory object. This may be performed for multiple updated object instances in the new factory object, preferably each separately. For the case of new object instances, they are created by the new factory and pointers established to invoke them. A single factory object may include multiple updated objects from a class, and/or new object instances from different classes, and the update may be performed without the need to reboot the operating system.

Dynamic update mechanisms in operating systems

Systems, especially operating systems, are becoming more complex to the point where maintaining them by humans is becoming nearly impossible. Many corporations have recognized this trend and have begun investing in autonomic technology. Autonomic technology allows a piece of software to monitor, diagnose, and repair itself. This can be used for improved performance, reliability, maintainability, security, etc. Disclosed herein is a mechanism to allow operating systems to hot swap a piece of operating system code, while continuing to offer to the user the service which that code is providing. This can be used, for examples, to increase the performance of an application or to fix a detected security hole live without bringing the machine down. Some autonomic ability will be mandatory in next generation operating system for without it they will collapse under their own complexity. The invention offers a key component of being able to achieve autonomic computing.

Achieving autonomic behavior in an operating system via a hot-swapping mechanism

A method for managing requests for deferred updates to shared data elements while minimizing grace period detection overhead associated with determining whether pre-existing references to the data elements have been removed. Plural update requests that are eligible for grace period detection are buffered without performing grace period detection processing. One or more conditions that could warrant commencement of grace period detection processing are monitored while the update requests are buffered. If warranted by such a condition, grace period detection is performed relative to the update requests so that they can be processed. In this way, grace period detection overhead can be amortized over plural update requests while being sensitive to conditions warranting prompt grace period detection.

Growing community of inventors

White Plains, NY, United States of America

Jonathan Appavoo