Abstract: Methods and apparatus for a platform independent object to bind to and access platform dependent software are disclosed. According to one aspect of the present invention, a software object that includes a wrapper and an associated platform dependent software. The platform independent object calls the wrapper. The wrapper, in turn, directly calls the associated platform dependent method. In this way, a platform independent object accesses the platform dependent method by directly calling the wrapper associated with the method.

Abstract: A system and method for providing process persistence in a virtual machine are described. A virtual persistent heap may be provided. The virtual persistent heap may enable the checkpointing of the state of the computation of a virtual machine, including processes executing within the virtual machine, to a persistent storage such as a disk or flash device for future resumption of the computation from the checkpoint. The Virtual Persistent Heap also may enable the migration of the virtual machine computation states, and thus the migration of executing processes, from one machine to another. The saved state of the virtual machine heap may also provide the ability to restart the virtual machine after a system crash or shutdown to the last saved persistent state, and to thus restart a process that was running within the virtual machine prior to the system crash or shutdown to a checkpointed state of the process stored in the virtual persistent heap.

Abstract: Embodiments of message gates are described. A message gate is the message endpoint for a client or service in a distributed computing environment. A message gate may provide a secure endpoint that sends and receives type-safe messages. Gates may perform the sending and receiving of messages between clients and services using a protocol specified in a service advertisement. In one embodiment, the messages are eXtensible Markup Language (XML) messages. For a client, a message gate represents the authority to use some or all of a service's capabilities. Each capability may be expressed in terms of a message that may be sent to the service. Creation of a message gate may involve an authentication service that generates an authentication credential, and that may negotiate the desired level of security and the set of messages that may be passed between client and service. A message gate may perform verification of messages against a message schema to ensure that the messages are allowed.

Abstract: In a distributed computing environment, a message gate may be the message endpoint for a client or service to communicate with another client or service. Devices may have a gate factory (e.g. message endpoint constructor) that is trusted code on the device for generating gates based on XML message descriptions. The use of the gate factory may ensure that the gate it generates is also trusted code, and that the code is correct with respect to a service advertisement. A service advertisement may indicate, for a particular service, a message schema, service URI and authentication service URI. In one embodiment, the pieces the gate factory needs to construct a gate are the XML schema of the service and the URI of the service. In another embodiment, an authentication credential may also be obtained and used in gate construction by running an authentication service specified in the service advertisement.

Abstract: A cluster implements a virtual disk system that provides each node of the cluster access to each storage device of the cluster. The virtual disk system provides high availability such that a storage device may be accessed and data access requests are reliably completed even in the presence of a failure. To ensure consistent mapping and file permission data among the nodes, data are stored in a highly available cluster database. Because the cluster database provides consistent data to the nodes even in the presence of a failure, each node will have consistent mapping and file permission data. A cluster transport interface is provided that establishes links between the nodes and manages the links. Messages received by the cluster transports interface are conveyed to the destination node via one or more links. The configuration of a cluster may be modified during operation.

Abstract: A system and method for searching for Internet-based repositories within a distributed computing environment are provided. A client on a device may interact with a search service on the same or a different device to find spaces (i.e., network-accessible XML object repositories) for storage and/or retrieval of data. The client may send an XML search request to the search service. The search request may include one or more desired characteristics, such as keywords, which are sought of a space. Based upon the search request, the search service may generate search results including locations (e.g., URIs) of one or more resulting spaces. The spaces may include web pages. In generating the search results, the search service may interact with a network-accessible third-party search engine, such as a browser-accessible search engine. The search service may obtain a service advertisement for each of the resulting spaces. Each service advertisement includes information which is usable to access the respective space.

Abstract: A caching mechanism for a virtual persistent heap. A feature of a virtual persistent heap is the method used to cache portions of the virtual persistent heap into the physical heap. The caching mechanism may be effective with small consumer and appliance devices that typically have a small amount of memory and that may be using flash devices as persistent storage. In the caching mechanism, the virtual persistent heap may be divided into cache lines. A cache line is the smallest amount of virtual persistent heap space that can be loaded or flushed at one time. Caching in and caching out operations are used to load cache lines into the heap or to flush dirty cache lines into the store. Different cache line sizes may be used for different regions of the heap. Translation between a virtual persistent heap address and the heap may be simplified by the caching mechanism.

Abstract: A method and system for garbage collecting a virtual heap using nursery regions for newly created objects to reduce flushing of objects from an in-memory heap to a store heap is provided. The garbage collection method is suited for use with small consumer and appliance devices that have a small amount of memory and may be using flash devices as persistent storage. The garbage collection method may provide good performance where only a portion of the virtual heap may be cached in the physical heap. The virtual heap may use a single address space for both objects in the store and the in-memory heap. In one embodiment, a single garbage collector is run on the virtual heap address space. The garbage collection method may remove non-referenced objects from the virtual heap. The garbage collection method may also include a compaction phase to reduce or eliminate fragmentation, and to improve locality of objects within the virtual heap.

Abstract: A caching mechanism for a virtual persistent heap is described. A feature of a virtual persistent heap is the method used to cache portions of the virtual persistent heap into the physical heap. The caching mechanism may be effective with small consumer and appliance devices that typically have a small amount of memory and that may be using flash devices as persistent storage. In the caching mechanism, the virtual persistent heap may be divided into cache lines. A cache line is the smallest amount of virtual persistent heap space that can be loaded or flushed at one time. Caching in and caching out operations are used to load cache lines into the heap or to flush dirty cache lines into the store. Different cache line sizes may be used for different regions of the heap. Translation between a virtual persistent heap address and the heap may be simplified by the caching mechanism. All references may be kept in one address space, the virtual persistent heap address space.

Abstract: Methods and apparatus for a cooperative processing of a task in a multi-threaded computing system are disclosed. In one aspect of the invention, a first thread is arranged to receive a task and only partially process the task. During its processing, the first thread stores processing information that is relevant to future processing in a packet that is associated with the task. Upon completing its processing, the first thread designates a second thread as the owner of the packet. After the second thread obtains ownership of the packet it then further processes the task based at least in part upon the processing information stored in the packet by the first thread. With the described arrangement no synchronization primitives are required for the threads to cooperate in processing the task.

Abstract: System and method for facilitating communications between peers in a peer-to-peer environment and network email clients. In one embodiment, network nodes including peer nodes may host mail transfer agents. The mail transfer agents may act as bridges between peer-to-peer protocols and email communication protocols. The mail transfer agents may communicate with peers according to peer-to-peer protocols and with email clients according to email communications protocols. Peers may communicate with mail transfer agents to send peer-to-peer messages to email clients. Email clients may communicate with the mail transfer agents to send email messages to and receive email messages from other email clients via the peer-to-peer network and to obtain peer-to-peer messages from peers.

Abstract: Embodiments of a shared resource distributed index mechanism that peers in a peer-to-peer network may utilize to distribute index entries corresponding to resources to indexes of shared resources among one or more other peers. These indexes may be used to direct queries to peers where the queries are most likely to be answered. When a query is received by a rendezvous peer including one or more indexes, contents of the query may be “looked up” in the index to find matches. The results of the lookup may include information on one or peer(s) that may hold advertisement(s) to the resource requested by the query. The query may then be forwarded to one or more peers that may hold the advertisement for the resource. Embodiments may provide “loosely-coupled” distribution of index entries for use in querying for resources in the peer-to-peer network.

Abstract: System and method for providing multiple embodiments of abstract software modules in peer-to-peer network environments. A module class may have one or more module specifications. Each module specification may have one or more module implementations configured to execute within a particular execution environment. A unique module class identifier may be assigned to the module class. A role extension to the module class identifier may be generated for each instance of the module class that performs a different role in a context. A module specification advertisement may be generated for each module specification. A unique module specification identifier may be assigned to each module specification of the module class. A module implementation advertisement may be generated for each module implementation. In one embodiment, the module specification identifier of the corresponding module specification is included in each module implementation advertisement.

Abstract: System and method for describing and identifying abstract software modules in peer-to-peer networking environments. A module class may have one or more module specifications. Each module specification may have one or more module implementations. A module class advertisement may be generated for the module class. A unique module class identifier may be assigned to the module class. A role extension to the module class identifier may be generated for each instance of the module class that performs a different role in a context. A unique module specification identifier may be assigned to each module specification of the module class. In one embodiment, a module specification advertisement may be generated for each module specification. In one embodiment, there may be one or more module implementations for each module specification. In one embodiment, a module implementation advertisement may be generated for each module implementation.

Abstract: System and method for multiplatform implementation of abstract software modules in peer-to-peer networking environments. A module class may have one or more module specifications. Each module specification may have one or more module implementations configured to execute within a particular execution environment. A unique module class identifier may be assigned to the module class. A unique module specification identifier may be assigned to each module specification of the module class. In one embodiment, a module specification advertisement may be generated for each module specification. A module implementation advertisement may be generated for each module implementation. In one embodiment, the module specification identifier of the corresponding module specification is included in each module implementation advertisement.

Abstract: A system and method for searching for documents within spaces in a distributed computing environment are provided. A client sends a lookup message to a space which stores documents. The lookup message may specify desired characteristics, such as a name or partial XML schema, of the stored documents. The documents may include XML service advertisements and XML device advertisements as well as general-purpose XML documents. A set of zero or more documents which match the lookup message are discovered. In one embodiment, the lookup message may include a desired name. If the lookup message includes both a desired name and a desired schema, the set of discovered documents may include both discovered documents having a name that matches the desired name and discovered documents having a schema that matches the desired schema. If the lookup message includes neither a desired name nor a desired schema, the set of discovered documents may include substantially all the documents stored in the space.

Abstract: The present invention provides a means to support new and modified platforms without the need to modify the system software kernel. The invention uses an approach referred to as Platform Service Agents (PSAs). The PSA works with the bus manager of the system software for that platform variant and modifies the system resources as needed. The PSA isolates specifics of the platform, so that the bus manager need not be modified. Because the PSAs themselves are outside of the kernel, are downloadable, and easily created for platform variants, new platforms can be supported without modification or re-release of the system software kernel.

Abstract: A method and system for providing an intelligent intermediate form of an object-oriented database. The intermediate form is derived from a grammatical form of an object-oriented database through the process of compilation. The grammatical form is a persistent form of an object-oriented database expressed in a human-readable and human-editable textual form according to a grammar. The intermediate form comprises an array of intelligent entry objects which encapsulate data with methods for manipulating that data. The methods include creating a database entry, creating a property associated with an entry, creating an attribute associated with an entry or property, querying the last entry, property, or attribute created, and finalizing entry storage. The intermediate form lacks the infrastructure of the database, but the intermediate form can be used to populate the object-oriented database with entries.

Abstract: A method and system for customizing the transformation of an object-oriented database to and from a grammatical form. A grammatical form is an expression of an object-oriented database in a textual form according to a grammar. The transformation customizer is a plug-in which provides translation of primitive data types to and from complex data types for compilation and serialization processes. A complex data type is defined in terms of one or more primitive data types. One or more values in the object-oriented database are expressed in terms of the complex data type. During serialization, the plug-in module is invoked. The plug-in understands both the complex data type and the primitive data types. The values from the object-oriented database are translated from the complex data type to the primitive data types. For customizing compilation, one or more values expressed in terms of the primitive data types are translated to the complex data type when the plug-in is invoked.

Abstract: A method and system for serializing a transient object-oriented database into a persistent form. The persistent form is a grammatical form, an expression of an object-oriented database in a textual form according to a grammar. The grammatical form is human-readable and human-editable. The grammar is designed to be platform-independent and programming-language-independent and therefore descriptive of any hierarchical object-oriented database. An object-oriented database is expressed as a plurality of entries in a transient, hierarchical, object-oriented form. The tree of entries is navigated and each entry is written to the persistent form as text according to the grammar. The serialized form stores only the key state of the database, not a “snapshot” of memory. Therefore, the persistent, serialized form is smaller than the in-memory, transient form of the object-oriented database.