Oracle America, Inc.

Sun Microsystems, Inc.

Facebook, Inc.

Oracle International Corporation

Michael H Paleczny

Christopher A Vick

Olaf Manczak

Jay R Freeman

Phyllis E Gustafson

Clifford N Click

Ali-Reza Adl-Tabatabai

Guilherme De Lima Ottoni

Yuguang Wu

Miguel Angel Lujan Moreno

Gregory M Wright

Amir Meir Michael

Lawrence G Votta

Bo Yang

Eric J Kustarz

Miguel-Angel Lujan Moreno

Disclosed here are methods, systems, paradigms and structures for optimizing intermediate representation (IR) of a script code for fast path execution. A fast path is typically a path that handles most commonly occurring tasks more efficiently than less commonly occurring ones which are handled by slow paths. The less commonly occurring tasks may include uncommon cases, error handling, and other anomalies. The IR includes checkpoints which evaluate to two possible values resulting in either a fast path or slow path execution. The IR is optimized for fast path execution by regenerating a checkpoint as a labeled checkpoint. The code in the portion of the IR following the checkpoint is optimized assuming the checkpoint evaluates to a value resulting in fast path. The code for handling situations where the checkpoint evaluates to a value resulting in slow path is transferred to a portion of the IR identified by the label.

Optimizing intermediate representation of script code for fast path execution

Disclosed here are methods, systems, paradigms and structures for optimizing generation of intermediate representation (IR) for a script code by eliminating redundant object reference count operations from the IR. An IR of the script includes (a) a set of first code that increments a reference count of an object when a programming construct refers to the object, and (b) an associated set of second code which decrements the reference count of the object when a reference to the object is removed. The IR is analyzed to identify a subset of the set of second code which, upon execution, does not decrement the reference count of the object to a zero value. The subset of second code and the first code corresponding to the subset is removed from the IR to generate an optimized IR. The optimized IR is further converted to an executable code.

Optimizing intermediate representation of script code by eliminating redundant reference count operations

Disclosed here are methods, systems, paradigms and structures for optimizing intermediate representation (IR) of a script code for atomic execution. Atomic execution of the script is achieved by generating portions of the IR as an atomic transaction. In an atomic transaction, a series of operations either all execute, or none executes. The IR includes checkpoints that evaluate to one of two possible values. The checkpoint evaluates to a first value when there is no error during execution, and evaluates to a second value when an error occurs. The IR is optimized for atomic execution by regenerating a portion of the IR including the checkpoint and code associated with the checkpoint as a transaction. When an error occurs during the execution of the transaction, the transaction is aborted and a state of execution of the script code is reverted to a state prior to the beginning of the transaction.

Optimizing intermediate representation of script code for atomic execution

A method for memory protection in a multiprocessor system, involving receiving a request at a first carrier to perform a memory operation at a memory address, wherein the first carrier receives the request from a processor, determining by the first carrier whether the processor is permitted to access memory at the memory address using a carrier identification (ID) of a second carrier, wherein the second carrier is associated with a memory controller used to access the memory, and sending the request to the second carrier, if the processor is permitted to access the memory.

Method and system for memory protection by processor carrier based access control

In a data center that cools servers using an airflow from a central fan, rather than individual server fans, the cooling needs for each server are met by creating a sufficient pressure differential across each server. Because the pressure differential is the same for all of the servers, it is desirable to operate the data center such that each server needs the same pressure differential for proper cooling. Accordingly, a load balancer assigns tasks to the servers based on the known cooling needs of each server in order to balance the pressure differential needed to cool the server. This information may also be sent to the central fan to ensure that a sufficient pressure is created by the fan. Determining the cooling needs beforehand avoids spikes in server temperature, thereby enabling the servers to operate safely at a temperature closer to their maximum rated temperatures.

Load balancing tasks in a data center based on pressure differential needed for cooling servers

A method for executing an application on multiple nodes includes synchronizing a first clock of a first node and a second clock of a second node, configuring a first hypervisor on the first node to execute a first application domain and a first privileged domain, and configuring a second hypervisor on the second node to execute a second application domain and a second privileged domain. Configuring the hypervisor includes allocating a first number of cycles of the first clock to the first privileged domain. Configuring the second hypervisor includes allocating the first number of cycles of the first clock to the second privileged domain. The method further includes executing the application in the first application domain and the second application domain. The first application domain and the second application domain execute semi-synchronously and the first privileged domain and the second privileged domain execute semi-synchronously.

Method and system for coordinating hypervisor scheduling

A method and apparatus for preserving contents of a volatile memory when a main (e.g., AC) power source is disconnected. The apparatus comprises flash memory, a controller for writing to the flash memory and a temporary power source. The temporary power source may be a relatively low power battery or supercapacitor. The apparatus is removably attached to a computing device (e.g., via a USB port). When main power of the device is disconnected, the temporary power source provides power for the apparatus, the volatile memory containing data to be safeguarded, and sufficient processing resources to transfer the data. For example, an auxiliary processor may be powered (instead of a relatively high-power processor) or just one core of a multi-core processor. Data are written to the apparatus and can be recovered when main power is reconnected. Or, the apparatus may be detached and attached to a different device for data recovery.

Method and apparatus for preserving memory contents during a power outage

A method for metadata management for scalable processes, involving creating a process by a first home processor, wherein the process is associated with a process identification (ID), storing the processor ID and information identifying the first home processor in a global process look-up data structure (GPLD), requesting metadata associated with the process, searching the GPLD to obtain the first home processor of the process using the process ID, and retrieving the metadata associated with the process from the first home processor.

Metadata management for scalable process location and migration

The functionality of a virtualization layer interposed between computer system hardware and a plurality of applications can be altered by pluggable extensions. According to one embodiment of the present invention, a virtualization layer is divided into a privileged portion and an unprivileged portion. While the privileged portion remains untouched, the functionality of the unprivileged portion can be modified by one or more pluggable extensions. Furthermore, file images operating on top of the virtualization layer, and in some cases unaware of the virtual nature of the virtualization layer, can be supplemented using pluggable extensions.

Pluggable extensions to virtual machine monitors

A system and method for allocating the nearest available physical memory in a distributed, shared memory system. In various embodiments, a processor node may broadcast a memory request to a first subset of nodes connected to it via a communication network. In some embodiments, if none of these nodes is able to satisfy the request, the processor node may broadcast the request to additional subsets of nodes. In some embodiments, each node of the first subset of nodes may be removed from the processor node by one network hop and each node of the additional subsets of nodes may be removed from the processor node by no more than an iteratively increasing number of network hops. In some embodiments, the processor node may send an acknowledgment to one node that can fulfill the request and a negative acknowledgement to other nodes that can fulfill the request.

Proximity-based memory allocation in a distributed memory system

A method for detecting a dependence violation in an application that involves executing a plurality of sections of the application in parallel, and logging memory transactions that occur while executing the plurality of sections to obtain a plurality of logs and a plurality of temporary results, where the plurality of logs is compared while executing the plurality of sections to determine whether the dependence violation exists.

Using police threads to detect dependence violations to reduce speculative parallelization overhead

A method for executing an application on a plurality of nodes, that includes synchronizing a first clock of a first node of the plurality of nodes and a second clock of a second node of the plurality of nodes, configuring a first hypervisor on the first node to execute a first application domain and a first privileged domain, configuring a second hypervisor on the second node to execute a second application domain and a second privileged domain, and executing the application in the first application domain and the second application domain, wherein the first application domain and the second application domain execute semi-synchronously and the first privileged domain and the second privileged domain execute semi-synchronously.

A virtual configuration system, comprising a virtualization engine and a configuration engine, for the dynamic instantiation of configuration files is disclosed. A mechanism is disclosed that allows for transactional updates to a repository of configuration settings comprising multiple files. Configuration entries are stored in a first memory location and a copy of the entries is stored in a second memory location. A virtual configuration file that includes a virtual configuration for each entry is created and used to provide the operating system with path and location information regarding the configuration entries. Simultaneously and during run-time of the computer, the configuration entries stored in the second memory location can be modified. Once the modifications are complete, a second virtual configuration file is created referencing the configuration entries stored at the second memory location. The first virtual configuration file is thereafter atomically replaced by the second virtual configuration file.

Growing community of inventors

Sunnyvale, CA, United States of America

Michael H Paleczny