International Business Machines Corporation

John Gerard Nistler

Steven Jay Munroe

James William Stopyro

Mark Douglas Schroeder

Maynard Paul Johnson

Robert Carl Seemann

A method, apparatus, system, and signal-bearing medium that in an embodiment collect profile information about class-type checks, calculate a number of class-type checks that minimizes a cost of inlining, generate inline code for the number of class-type checks for a site in a method, and sort the inline code based on a frequency of the class types. Any remaining class-type checks at the site that are not handled by the inlined class-type checks are handled via an out-of-line function call. In this way, inlined code is used when it provides better performance than an out-of-line function, and the out-of-line function call is used when it provides better performance than the inlined code.

Determining how many class-type checks to inline

An object oriented mechanism and method provide exact information about the current invocation stack even when methods are inlined. A virtual stack frame mechanism determines whether a called method has been inlined, and counts both virtual frames and real frames when determining information corresponding to a called method. The virtual stack frame mechanism is preferably implemented in an object oriented class that provides methods for determining information corresponding to a called method.

Object oriented apparatus and method for preserving stack frame identity during inlined method calls

A preferred embodiment of the present invention provides an intelligent reference object (IRO), which is used to encapsulate address translation between shared address space (SAS) addresses and native system addresses. The IRO works with a shared persistent virtual storage system that provides address translation between SAS addresses and the underlying system. By encapsulating these addresses translations in an IRO, the preferred embodiment provides the ability to create and share persistent objects using single level store semantics. When a client accesses the data in a persistent object, the IRO corresponding to the persistent object provides any address translation and indirection needed to perform the access.

Method and apparatus for encapsulating address translation for shared persistent virtual storage

The preferred embodiment of the present invention facilitates the creation, storage and interaction of persistent objects using single level storage semantics on commodity systems. Specifically, the present invention defines several objects used to implement persistent objects in a shared address space. The preferred embodiment includes a Class Encapsulator class and the Object Encapsulator class that are preferably designed to encapsulate the class data and instance data, respectively. In particular, a Class Encapsulator object would preferably be created in a Persistent Container for each class of objects loaded into that Persistent Container. The Class Encapsulator object would include all of the specific data needed to implement its corresponding class. Likewise, an Object Encapsulator object would preferably be created to encapsulate each object to be stored persistently in the shared address space. A Persistent Handle class is preferably defined to store the shared address space address of the Class Encapsulator object and the Object Encapsulator object.

Virtual machine implementation for shared persistent objects

The preferred embodiment of the present invention facilitates the creation, storage and interaction of persistent objects using single level storage semantics on commodity systems. The preferred method and apparatus utilize a persistence mechanism to provide object persistence. In particular, the persistence mechanism defines a Factory class, a Finder class, an ExpandingContainer class, a Container class and a ClassLoader class which work together to create persistent shared objects. An application can create persistent objects by calling methods on the Factory class. The Factory class then works in conjunction with an instance of the Container class and the ClassLoader class to create persistent objects in a shared address space (SAS). Shared address space is a persistent virtual address space shared by all processes running on a computer system. The SAS allows the processes to access data within SAS at any time, using a SAS address.

System and method for storage of shared persistent objects

The preferred embodiment present invention provides a shared persistent virtual storage system and method for creating and managing a large logical virtual address space, called a shared address space (SAS), on existing systems. The shared persistent virtual storage system provides an interface layer between client processes using the SAS addresses and the underlying system. By providing the ability to use a large shared address space, the preferred embodiment allows the creation and sharing of persistent objects using single level store semantics. The preferred embodiment does this by mapping the shared address space to backing store as needed, and by implicitly moving portions of data, called pages, between backing storage and main memory as needed by client process. The preferred embodiment then provides a mechanism for translating shared address space addresses into a native address of the data in the page cache and providing that address to the application. Thus, the preferred embodiment provides the ability to store data using proven single level storage techniques in commodity systems that use smaller native addressing. This data can then be easily shared between client processes using the shared address space addresses.

Growing community of inventors

Rochester, MN, United States of America

John Gerard Nistler