Abstract: A method for configuring software modules that includes accessing a properties repository that includes a plurality of properties of the execution environment of the computer system. The method further includes generating a configuration file for each software module. Generating a configuration file includes obtaining a generator module defined for the software module, and executing the generator module to instantiate the configuration file for the software module. The generator module is configured to identify a property required for the configuration file, obtain the value for the property from the properties repository, and store the value for the property in the configuration file in accordance with a customized format required by the software module. The method further includes storing the configuration file for each of the software modules.

Abstract: A method for committing memory transactions in an application that includes executing a plurality of sections of the application in parallel, logging a plurality of memory transactions that occur while executing the plurality of sections to obtain a plurality of logs and a plurality of temporary results, wherein the plurality of memory transactions that includes a plurality of writes to at least one memory location, comparing the plurality of logs to identify an optimal list of writes from the plurality of writes, and committing memory transactions corresponding to a subset of the plurality of temporary results, wherein the subset of the plurality of temporary results is identified by the optimal list of writes.

Abstract: A computer system may be configured to dynamically select a memory virtualization and corresponding virtual-to-physical address translation technique during execution of an application and to dynamically employ the selected technique in place of a current technique without re-initializing the application. The computer system may be configured to determine that a current address translation technique incurs a high overhead for the application's current workload and may be configured to select a different technique dependent on various performance criteria and/or a user policy. Dynamically employing the selected technique may include reorganizing a memory, reorganizing a translation table, allocating a different block of memory to the application, changing a page or segment size, or moving to or from a page-based, segment-based, or function-based address translation technique.

Abstract: A method for distributively storing a data object on a data storage system includes determining a layout map ID and associating the layout map ID with the data object. The layout map ID is used in determining a layout map, and the layout map is used in determining a layout given a current configuration of the data storage system. The data object is fragmented into data fragments and parity fragments, and the data fragments and parity fragments are distributively stored on data storage system in accordance with the layout.

Abstract: A virtual file system is formed configured to enable the dynamic composition of immutable file system images. A file system containing a software distribution is divided into a plurality of mutually exclusive sub-trees. Each sub-tree includes a portion of the software distribution. An immutable file system image is formed for each sub-tree. During the booting of an operating system, a virtualization engine intercedes in the boot process to mount the immutable file system images to independent directories of the root file system. Upon request the virtualization engine, during run-time, combines virtual entries corresponding to immutable file system images so as to resemble the original software distribution.

Abstract: 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.

Abstract: 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.

Abstract: Incoming requests to a data storage system are distributed among one or more peer node computer systems of the data storage system in accordance with a load spreading configuration. A hash value is computed from the request utilizing selected header information of the request. The hash value is utilized in selecting a peer node computer system to receive the request in accordance with the load spreading configuration, and the request is redirected to the selected peer node computer system. In one embodiment, the load spreading configuration is implemented at a layer 2 switch and the load spreading configuration is reconfigurable by a peer node computer system of the data storage system.

Abstract: A method for translating memory addresses in a plurality of nodes, that includes receiving a first memory access request initiated by a processor of a first node of the plurality of nodes, wherein the first memory access request comprises a process virtual address and a first memory operation, translating the process virtual address to a global system address, wherein the global system address corresponds to a physical memory location on a second node of the plurality of nodes, translating the global system address to an identifier corresponding to the second node, and sending a first message requesting the first memory operation to the second node based on the identifier, wherein the second node performs the first memory operation on the physical memory location.

Abstract: A method for installing a device driver for a device in a guest domain, that includes obtaining a first device driver for the device by a hypervisor, installing, by the hypervisor, the first device driver into memory allocated to the guest domain, and notifying an operating system in the guest domain of the first device driver after installing the device driver, wherein the operating system communicates with the device using the first device driver.

Abstract: 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, wherein configuring the hypervisor comprises allocating a first number of cycles of the first clock to the first privileged domain, configuring a second hypervisor on the second node to execute a second application domain and a second privileged domain, wherein configuring the second hypervisor that includes allocating the first number of cycles of the first clock to the 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.

Abstract: A disk is divided into K angular regions. A log write request is replicated K times and K number of identical log writes are issued to the disk to be written to each of the angular regions of the log. Upon completion of the first write, the application requesting the log write is informed of its completion resulting in a reduction of rotational latency by a factor of K.

Abstract: A system for mapping memory of a computer system includes a sorter, a partitioner, and a mapper. The sorter sorts a physical memory space to obtain a sorted virtual memory space, where the physical memory space includes a plurality of memory patterns, wherein each of the plurality of memory patterns is associated with a physical device and includes at least one memory block, wherein the at least one memory block is contiguous and addressable, and the plurality of memory patterns are arranged based on a predefined number of occurrences of each memory pattern, size of contiguous memory address ranges in each of the plurality of memory patterns, size of contiguous memory address ranges in each of the plurality of memory patterns, and arrangement of contiguous address ranges in each of the plurality of memory patterns.

Abstract: A method for traversing a file system tree on a storage device includes obtaining a list of entries within a directory of the file system tree. The list of entries is sorted in order of the file locations on the storage device. The entries within the list of entries are accessed for tree traversal in order in which they are sorted.

Abstract: 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.

Abstract: A method for committing memory transactions in an application that includes executing a plurality of sections of the application in parallel, logging a plurality of memory transactions that occur while executing the plurality of sections to obtain a plurality of logs and a plurality of temporary results, wherein the plurality of memory transactions that includes a plurality of writes to at least one memory location, comparing the plurality of logs to identify an optimal list of writes from the plurality of writes, and committing memory transactions corresponding to a subset of the plurality of temporary results, wherein the subset of the plurality of temporary results is identified by the optimal list of writes.

Abstract: A system for mapping memory of a computer system includes a sorter, a partitioner, and a mapper. The sorter sorts a physical memory space to obtain a sorted virtual memory space, where the physical memory space includes a plurality of memory patterns, wherein each of the plurality of memory patterns is associated with a physical device and includes at least one memory block, wherein the at least one memory block is contiguous and addressable, and the plurality of memory patterns are arranged based on a predefined number of occurrences of each memory pattern, size of contiguous memory address ranges in each of the plurality of memory patterns, size of contiguous memory address ranges in each of the plurality of memory patterns, and arrangement of contiguous address ranges in each of the plurality of memory patterns.

Abstract: A computer system may be configured to dynamically select a memory virtualization and corresponding virtual-to-physical address translation technique during execution of an application and to dynamically employ the selected technique in place of a current technique without re-initializing the application. The computer system may be configured to determine that a current address translation technique incurs a high overhead for the application's current workload and may be configured to select a different technique dependent on various performance criteria and/or a user policy. Dynamically employing the selected technique may include reorganizing a memory, reorganizing a translation table, allocating a different block of memory to the application, changing a page or segment size, or moving to or from a page-based, segment-based, or function-based address translation technique.

Abstract: A computer system employing memory virtualization may employ a function-based technique for virtual-to-physical address translation. A function-based translation technique may involve replacing a generic trap handler and one or more translation table look-ups with a function to compute a corresponding physical address from a given virtual address. The computer system may be configured to determine a translation function dependent on mappings in one or more translation tables. The computer system may be configured to reorganize a memory, to reorganize one or more translation tables, or to allocate different blocks of memory to an application prior to determining a translation function. Different applications or threads executing on the computer system may employ different translation functions. Different regions of memory may be accessed using different translation functions. Some virtual addresses may be translated using a function while others may be translated using one or more translation table look-ups.

Abstract: The use of a token-based memory protection technique may provide memory protection in a computer system employing memory virtualization. A token-based memory protection technique may include assigning a unique identifier to an application, process, or thread, and associating the identifier with a block of memory allocated to that application, process, or thread. Subsequent to assigning the identifier, a packet requesting access to that block of memory may include a token to be compared to the identifier. A memory controller may be configured to associate the identifier with the block of memory and to compare the token in the memory request packet to the identifier before granting access. If a second block of memory is subsequently allocated to the application, process, or thread, the identifier may be disassociated with the first block of memory and associated with the second block of memory.