Abstract: A predictive memory performance optimizing unit for use with an interleaved memory, for example a DDR SDRAM memory, and suitable for use in a computer graphics system, among others, is described. The unit maintains a queue of pending requests for data from the memory, and prioritizes precharging and activating interleaves with pending requests. Interleaves which are in a ready state may be accessed independently of the precharging and activation of non-ready interleaves. The unit utilizes idle cycles occurring between consecutive requests to activate interleaves with pending requests.

Abstract: A technique is provided for reducing the number of write barriers executed in mutator code without compromising garbage collector performance. Advantageously, a compiler generates two forms of a mutator code—a first version with write barriers and a second version substantially without write barriers. In operation, the first version of the code may be accessed by a vtable in a “mature” near-class and the second version may be accessed by a vtable in a “nascent” near-class. According to the invention, mapping of functionally equivalent points in the first and second versions of the mutator code may be facilitated by an associated pcmap. Further, each of the first and second versions may also be associated with a respective nr_map that facilitates mapping functionally equivalent points within different branches of guard code sequences corresponding to reference-writes to non-receiver objects.

Abstract: A standard for security management in a client server computer system is disclosed. In one aspect, the present invention specifies a security contract between an application server and a resource adapter, supporting access to an enterprise information system by passing a connection request from the resource adapter to the application server, propagating a a security context from the application server to the resource adapter. The security contract includes a subject class representing a grouping of related information for a single entity, and security-related attributes of the subject class.

Abstract: A mechanism is provided for causing a transaction to fail at a predetermined transaction state. A transaction coordinator is instructed to process a transaction until the transaction has reached a predetermined transaction state. The transaction coordinator is caused to fail while the transaction is in the predetermined transaction state. Failure of the transaction at the predetermined transaction state is thereby effectuated.

Abstract: Use of a policy object for verification in a distributed system. A machine downloads a policy object containing a reference to code governing verification of data. The machine uses the reference to obtain the code and locally verify data or other information. As particular rules for the data change, the policy object may be updated to provide a reference to the code for the new rules when it is downloaded.

Abstract: A modular parser architecture and methods related thereto make use of a number of miniparsers. Each miniparser is capable of receiving input and generating an output dependent thereon. In one embodiment, a lexer or a miniparser capable of lexical analysis receives certain code and provides an abstract syntax tree. Each miniparser performs operations on a set of syntactical constructs to produce a corresponding output syntax tree, which in turn may become an input syntax tree for a next miniparser which may operate on a different set of syntactical constructs.

Abstract: A method, apparatus, and system for providing a standard, generic contract between an application server and a message provider which allows the message provider to deliver messages to message endpoints (each of which is associated with a corresponding message application) residing in the application server is disclosed. By generic, it is meant that the contract is independent of the specific messaging style, messaging semantics and messaging infrastructure used to deliver messages. In this way, the contract also serves as the standard message provider pluggability contract that allows any message provider to be plugged into any application server via an associated resource adapter.

Abstract: A handheld computing device is used to copy files from the screen of a fixed computer. The display of the handheld device is linked to that of the underlying computer and file and directory icons together with their underlying files are copied to the handheld device. Files from the handheld device can also be transferred to the fixed computer. When a user is running a program on the fixed computer, he may capture the state of that computer and transfer everything needed to permit execution of that program to continue uninterrupted on the handheld device. Thus files and executing programs may be lifted from the fixed computer and used on the handheld device.

Abstract: One embodiment of the present invention provides a system that facilitates selectively unmarking load-marked cache lines during transactional program execution, wherein load-marked cache lines are monitored during transactional execution to detect interfering accesses from other threads. During operation, the system encounters a release instruction during transactional execution of a block of instructions. In response to the release instruction, the system modifies the state of cache lines, which are specially load-marked to indicate they can be released from monitoring, to account for the release instruction being encountered. In doing so, the system can potentially cause the specially load-marked cache lines to become unmarked. In a variation on this embodiment, upon encountering a commit-and-start-new-transaction instruction, the system modifies load-marked cache lines to account for the commit-and-start-new-transaction instruction being encountered.

Abstract: One embodiment of the present invention provides a system that uses a block-partitioned technique to efficiently solve a system of linear equations. The system first receives a matrix that specifies the system of linear equations to be used in performing a time-based simulation. This matrix includes a static portion containing entries that remain fixed over multiple time steps in the time-based simulation, as well as a dynamic portion containing entries that change between time steps in the time-based simulation. Next, the system performs the time-based simulation, wherein performing the time-based simulation involves solving the system of linear equations for each time step in the time-based simulation. In solving the system of linear equations, the system factorizes the static portion of the matrix only once, and reuses the factorization of the static portion in performing an overall factorization of the matrix for each time step of the time-based simulation.

Abstract: A method of identifying applications installed on a customer computer system by collecting signature information associated with installed binaries. The binaries are precisely identified by comparing the collected signature information to previously stored signatures. In a specific implementation the signatures comprise MD5 signatures.

Abstract: The propagation of a feedback signal, such as a DQS signal generated in response to a read request in a Double Data Rate (DDR) memory system, into a digital host system, such as an ASIC, is controlled by using a programmable delay circuit and detection sequence to compensate for variable I/O delay. The memory system includes a controller and an interface, both on the ASIC, and memory units coupled to the controller through the interface. The interface uses the read request signal, sent by the controller to initiate read operations, to generate a select signal. A programmable delay element inside the interface unit is programmed using a delay value generated by a delay manager unit inside the controller. The programmable delay element delays the select signal, and an enable signal is generated from the delayed select signal, using DQS. The propagation of DQS is controlled by the enable signal.

Abstract: A directory server system that includes a data repository storing a plurality of entries, wherein the plurality of entries comprises a plurality of user entries and a plurality of role entries, wherein each of the plurality of role entries define a role and comprises an InterestedApplication attribute, a directory server executing a first operation to obtain initial results and execute a second operation to obtain final results, wherein the second operation uses the initial results and the InterestedApplication attribute to obtain the final results, and an application requesting the directory server to execute the first operation and the second operation.

Abstract: A method includes adding direction to interference edges of a register interference graph and choosing a node of the register interference graph to spill based upon a pass degree of the node. By using the pass degree, the node that caused the greatest interference with allocation of the variables to the physical registers is preferentially chosen to be spilled.

Abstract: It has been discovered that initialization of a memory array can be improved by setting the nodes of the memory array to a predetermined value automatically upon applying power to the integrated circuit. Data input nodes and a memory write enable node are configured to store the predetermined values on the nodes of the memory array in response to successive enablement of word lines corresponding to the nodes of the memory array and automatic reset of the word lines. Circuitry included for initializing control and data signals of the memory array are effectively disabled upon termination of the initialization. Inclusion of circuitry that initiates and terminates the initialization obviates an additional input/output pin for this purpose.

Abstract: Methods and apparatus for enabling inconsistent or unsafe threads to efficiently reach a consistent or safe state when a requesting thread requests a consistent state are disclosed. According to one aspect of the present invention, a method for requesting a consistent state in a multi-threaded computing environment using a first thread includes acquiring a consistent state lock using the first thread, and identifying substantially all threads in the environment that are inconsistent. The state of the inconsistent threads is altered to a consistent state, and the first thread is notified when the states of the previously inconsistent threads have been altered to be consistent. Once the first thread is notified, the first thread releases the consistent state lock. In one embodiment, the method also includes performing a garbage collection after releasing the consistent state lock using the first thread.

Abstract: In a garbage collector that employs the train algorithm, the collector identifies cars that are located far back in the collection order but already have large remembered sets, and it advances their collection. One way of doing so includes advancing a car's nominal position in the collection order, placing it nominally ahead of erstwhile “older” cars as well as actually. Another way does not include changing the advanced car's nominal position. The advancement operation is simpler with the latter approach, but normal updating is simpler with the former. Although both approaches tend to increase the number of entries in the remembered set of the car thus advanced, they actually reduce the overall memory cost of remembered-set maintenance.

Abstract: A method of translating computer source code into optimized object code. The computer source code contains a first label statement defining a first label, a second label statement defining a second label, a third label statement defining a third label, and a computed goto statement for instructing a computer to branch to the first label or to the second label, but not to the third label. The method includes generating a list of labels contained within at least a portion of the computer source code. The list of labels includes the first label and the second label, but not the third label. The method also includes translating the computer source code into an intermediate language. The translation of the computer source code includes translating the computed goto statement into an indirect goto statement within the intermediate language. The method also includes generating object code that includes the first label and the second label but does not include the third label.

Abstract: A Negative Bias Temperature Instability (NBTI) tolerant sense amplifier is provided. The sense amplifier includes an input stage having a pair of balanced isolation devices. Each of the balanced isolation devices has an input connected to receive a separate one of a pair of differential input signals. Each of the balanced isolation devices also has a gate that is connected to receive a common bias voltage. The sense amplifier further includes a sense stage connected to the input stage. The sense stage is configured to receive and amplify a higher signal to be provided by the pair of balanced isolation devices. The sense amplifier is also equipped to operate a low voltage levels.

Abstract: One embodiment of the present invention provides a system that monitors a computer system using a plurality of physical sensors. The system operates by polling the plurality of physical sensors in a given sequence at a given rate, wherein each physical sensor monitors a specific physical parameter of the computer system. The system then provides a plurality of measurements from the plurality of physical sensors to a monitoring system. If a given physical sensor detects a parameter that is not within a pre-determined operating range, the system receives an interrupt from the given physical sensor. In response to receiving this interrupt, the system raises an alarm.