Abstract: A flag which is set to the on state when a process of writing data as a data file into a storage area which is permitted to be written only once results in failure is previously set in a data memory of an IC card. When a flag of a to-be-written EF specified by a write binary command is set to the on state, a control element of the IC card compares received data to be written to the EF with data which is already written to the data storage area of the EF. Based on the comparison result, the control element of the IC card rewrites data in the storage area in which the compared data items do not coincide with each other into the received data.

Abstract: Recovery processing is provided for management components of an Information Technology (IT) environment. The recovery processing recovers the components, as well as performs one or more tasks that were being performed by the components prior to recovery.

Abstract: A lock-based software transactional memory (STM) implementation may determine whether a transaction's write-set is static (e.g., known in advance not to change). If so, and if the read-set is not static, the STM implementation may execute, or attempt to execute, the transaction as a semi-static transaction. A semi-static transaction may involve obtaining, possibly after incrementing, a reference version value against which to subsequently validate that memory locations, such as read-set locations, have not been modified concurrently with the semi-static transaction. The read-set locations may be validated while locks are held for the locations to be written (e.g., the write-set locations). After committing the modifications to the write-set locations and as part of releasing the locks, versioned write-locks associated with the write-set locations may be updated to reflect the previously obtained, or newly incremented, reference version value.

Abstract: This invention is a system and method for backup and recovery of data using a new architecture that includes continuous backup and information protection backup and recovery system components.

Abstract: This invention is an architecture for backup and recovery of data including continuous backup and information protection backup and recovery system components.

Abstract: A distributed system for creating a checkpoint for a plurality of processes running on the distributed system. The distributed system includes a plurality of compute nodes with an operating system executing on each compute node. A checkpoint library resides at the user level on each of the compute nodes, and the checkpoint library is transparent to the operating system residing on the same compute node and to the other compute nodes. Each checkpoint library uses a windowed messaging logging protocol for checkpointing of the distributed system. Processes participating in a distributed computation on the distributed system may be migrated from one compute node to another compute node in the distributed system by re-mapping of hardware addresses using the checkpoint library.

Abstract: A slave device adapted to couple to a master processor and including an error handler and a communication controller. The error handler is configured to detect errors internal to the slave device and, in response to detecting at least one error and independent of the master processor, configured to select an error recovery operation based on the at least one detected error and to initiate and perform the selected error recovery operation. The communication controller is configured to communicate with the master processor according to a master/slave protocol, and configured to maintain the master/slave protocol during performance of the selected error recovery operation by the error handler.

Abstract: A method and apparatus are disclosed for performing maintenance operations in a system using address, data, and controls which are transported through the system, allowing for parallel and serial operations to co-exist without the parallel operations being slowed down by the serial ones. It also provides for use of common shifters, engines, and protocols as well as efficient conversion of ECC to parity and parity to ECC as needed in the system. The invention also provides for error detection and isolation, both locally and in the reported status. The invention provides for large maintenance address and data spaces (typically 64 bits address and 64 bits data per address supported).

Abstract: In accordance with an aspect of the present invention, in a data protection system having a production location, a storage location, and a communication path for transmitting data between the production location and the storage location, a method for creating a makeup archive job is provided. The method includes determining if a task of an archive job was successful and, if it is determined that the task was not successful, including the task in an archive makeup job. Additionally, the method determines if there are any tasks of the archive job that are dependent upon the failed task. If there are dependent tasks, those dependent tasks are also included in the archive makeup job.

Abstract: Embodiments include methods, apparatus, and systems for controlling of sparing in a storage system. In one embodiment, a method compares a first amount of time to complete sparing of data from a failed disk in a storage system with a second amount of time to complete a user request to the storage system in order to determine when to create a copy of the data from the failed disk.

Abstract: A method for diagnosing problems with protection of a data source and recovery of the same. The method includes diagnosing a copy of data located at the storage location and diagnosing a temporal version of the copy of data. Based on the diagnosis it is determined whether an error or a warning was detected. If either were detected a response is provided with a suggested solution.

Abstract: An undo operation is executed by an application by performing the inverse actions of the do operation to which the undo operation relates. Previous designs simply swapped memory to execute an undo operation according to code that was entirely dissimilar to the code of the do operation. The dissimilarity of the code caused debugging such operations to be difficult. Using the inverse action to undo an action results in the similar code for the do, undo, and redo operations. Also, undo atoms are logged for do, undo, and redo operations so that any exceptions thrown during an operation allows the application to return to a previous, consistent state by operating on the undo atoms.

Abstract: The present invention provides a method for optimizing the processing of backend transactions. The method operates by identifying a transaction group comprising related transactions for processing from a program executing on a computer and determining a degree of necessity for each of the related transactions, where the degree of necessity represents a predetermined time period given for each of the plurality of related transactions to successfully complete execution. The method includes determining which of the plurality of related transactions depend upon the successful completion of a transaction, assigning a priority for each of the related transactions, and scheduling the execution of the related transactions based upon priority. The method further includes canceling the execution of any of the related transactions that depend upon a transaction that does not successful complete execution, and returning to the program any data resulting from the execution of the related transactions.

Abstract: A data protection application if provided. The data protection application includes a job for providing protection to data. That job contains a plurality of tasks configured to perform the job. Also included is a task executor for managing the progress of each of the plurality of tasks.

Abstract: A method, system and program product for processing a transaction that requires multiple resources. The multiple resources for the transaction are concurrently prepared and/or committed. Further, a response can be sent to a requester before one or more of the resources has been committed. The resources can be prepared/committed using non-blocking function calls, using separate threads, or the like.

Abstract: Systems and methods in accordance with various embodiments can detect and alleviate potential or actual deadlock of a storage switch or storage area network when attempting to write data to a mirrored virtual target. In accordance with one embodiment, a timer is started when a storage switch routes a write command to the physical targets corresponding to a virtual target of the write command. If each physical target does not return a transfer ready resource within a predetermined timeout period, the switch determines that a potential or actual deadlock has occurred. An abort command is sent to each of the physical devices. The abort command can clear the command from the targets and also free any allocated transfer ready resources. After receiving an acceptance response from each physical target, the state of the write command at the switch can be cleared. The write command can then be re-issued to the physical devices.

Abstract: A digital broadcast file data receiving method and a digital broadcast file data receiving apparatus are provided. The digital broadcast file data receiving method and the digital broadcast file data receiving apparatus enable reception and display of proper broadcast file data by detecting an error in a specific data block and receiving the specific data block again in a process of receiving digital broadcast file data.

Abstract: A technique is described for guaranteeing recovery in a computer system comprising of recovery contracts with a plurality of obligations for a message exchange between a first component and a second component. Three forms of contract are described, governing interactions between three types of components. Each contract is bilateral, i.e. between a first component and a second component. The first and second components have mutual agreement on when the contract will be released to facilitate log truncation, and independent and/or autonomous recovery.

Abstract: A microcontroller comprising a central processing unit and a further fault processing unit suitable for performing validation of operations of said central processing unit. The further fault processing unit is external and different with respect to said central processing unit and said further fault processing unit comprises at least a module for performing validation of operations of said central processing unit and one or more modules suitable for performing validation of operations of other functional parts of said microcontroller. Validation of operations of said central processing unit is performed by using one or more of the following fault tolerance techniques: data shadowing; code&flow signature; data processing legality check; addressing legality check; ALU concurrent integrity checking; concurrent mode/interrupt check.

Abstract: A system and method in a data processing system for recovering data in a file system. A request to modify a data block in the file system is detected. In response to detecting the request to modify the data block, metadata describing the data block in the file system is written in a log. In response to detecting an error during the writing of the metadata, an error counter is incremented. Finally, in response to a request to recover the data in the file system, the metadata is read only if the error counter is less than or equal to a predetermined value.

Abstract: Provided are a method, system, and program for reassigning storage volumes from a failed processing system to a surviving processing system. A first processing system detects a failure of a second processing system. The first processing system determines device groups of storage devices managed by the failed second processing system and determines for each determined device group, hosts that connect to storage devices in the device group. The first processing system sends, for each device group, a unit check to each determined host indicating failure of each device group through one storage device in the device group to which the determined host connects. The determined hosts execute instructions to terminate any I/O operations in progress on the storage devices in the device group in response to the unit check indicating failure of one storage device in the device group and issue, a command to one storage device for the device group to end the busy condition.

Abstract: Persistent components are provided across both process and server failures, without the application programmer needing take actions for component recoverability. Application interactions with a stateful component are transparently intercepted and stably logged to persistent storage. A “virtual” component isolates an application from component failures, permitting the mapping of a component to an arbitrary “physical” component. Component failures are detected and masked from the application. A virtual component is re-mapped to a new physical component, and the operations required to recreate a component and reinstall state up to the point of the last logged interaction is replayed from the log automatically.

Abstract: Disclosed is a rollback-free method for performing multi-step procedures in the presence of possible failure. As the procedure proceeds from its initial state through transitions to its final state, its constituent transitions are monitored for failure. If a failure is detected, then the procedure is “sidetracked” into a recovery coordination state. From the recovery coordination state, the procedure is logically taken back to its initial state and retried. In this manner, the procedure is shepherded, without rollbacks, through its transitions until it successfully reaches its final state. In a particular embodiment, a multi-step procedure is developed for moving a resource from one resource server to another The steps of the procedure are designed so that all throughout the procedure, both of the resource servers and a directory server are kept synchronized. This allows client requests to proceed without interruption even during the resource movement.

Abstract: A method is designed for controlling a total mixing system including a first mixing system and a second mixing system, which are operated in a linked manner. In the method, the first mixing system stores first scene data specifying contents of a mixing process matching a scene. The second mixing system stores second scene data specifying contents of a mixing process matching a scene. The first mixing system transmits a scene recall request to the second mixing system when a recall event of the first scene data occurs. The second mixing system transmits back a recall enabling response to the first mixing system after receipt of the scene recall request. The first mixing system reconstructs the contents of the mixing process on the basis of the first scene data after the reception of the recall enabling response. The second mixing system reconstructs the contents of the mixing process on the basis of the second scene data after the transmission of the recall enabling response.

Abstract: Provided are a method, system, and program for reassigning storage volumes from a failed processing system to a surviving processing system. A first processing system detects a failure of a second processing system. The first processing system determines device groups of storage devices managed by the failed second processing system and determines for each determined device group, hosts that connect to storage devices in the device group. The first processing system sends, for each device group, a unit check to each determined host indicating failure of each device group through one storage device in the device group to which the determined host connects. The determined hosts execute instructions to terminate any I/O operations in progress on the storage devices in the device group in response to the unit check indicating failure of one storage device in the device group and issue, a command to one storage device for the device group to end the busy condition.

Abstract: A method for providing data integrity of a database system. A standby database is selected to replace a failed primary database. At least one redo log file having at least one data transaction is selected to be applied to the selected standby database. The selected standby database is updated with the data transaction from the selected redo log file if an identification code in the redo log file matches an identification code in the standby database.

Abstract: A process group resource manager for managing protected resources during transaction processing is disclosed. The process group resource manager comprises a first process configured to provide access to a protected resource during one or more transactions, the first process being further configured to construct a transaction record for each respective transaction, wherein each transaction record includes each request message received by the first process and each response message sent by the first process during a particular transaction. The process group resource manager further comprises a second process configured to serially replay the transactions in which the first process participates, the second process being configured to cause a particular transaction to rollback if the replay of that transaction does not match the transaction record constructed by the first process for that transaction.

Abstract: A method of performing a retry procedure may begin with detecting an error in a first zone of a data storage medium. Upon detecting the error, it is determined whether any retry procedure of a sequence of retry procedures has been performed upon detecting a previous error in the first zone. If a first retry procedure of the sequence was unsuccessfully performed upon detecting the previous error, there is performed a second retry procedure that follows next after the first retry procedure in the sequence.

Abstract: A memory device may include a memory cell array, a page buffer circuit, and/or a control logic. The page buffer circuit may include first and second registers and be configured to store data to be programmed in the memory cell array. The control logic may be configured to control the page buffer circuit to reload data stored in the first register into the second register in response to a reload command input if a program operation fails.

Abstract: The disclosed technology facilitates recovery from storage-related failures by checkpointing copy-on-write operation sequences. An operation sequence incorporating such checkpoints into a copy-on-write can include the following: receive a write request that identifies payload data to be written to a first data store, read original data associated with the first data store, copy the original data to a second data store, record transactional information associated with the write request, generate a first checkpoint to confirm the successful recordation of the transactional information and the successful copying of the original data to the second data store, write the payload data to the first data store, acknowledge a successful completion of the copy-on-write operation sequence, and generate a second checkpoint that confirms the successful completion of such operation sequence. The first and second checkpoints are used to form a pre-failure representation of one or more storage units (or parts thereof).

Abstract: A RAID capacity expansion interruption recovery handling method and system is proposed, which is designed for use with a RAID (Redundant Array of Independent Disks) unit for providing a capacity-expansion interruption recovery function that allows the RAID unit to recover after an event of an unexpected interruption to a capacity-expansion procedure that builds data from an original disk set to a newly-added disk. The proposed method and system is characterized by the capability of continuously recording the addresses of blocks that have been rebuilt in the original disk set and the newly-added disk to a permanent storage medium, such that in the event of any unexpected interruption, the address of the last block that has been rebuilt can be stored as a checkpoint. After the RAID unit is reset, the checkpoint can then be used as a recovery point for the uncompleted capacity expansion procedure without having to restart all over again from the beginning point.

Abstract: A system for detecting transmission errors in a data transmission system includes a receiver for receiving a data packet transmitted thereto by a corresponding transmitter and transmitting the data packet to a destination device and an error detection device for receiving a plurality of protocol signals that control the operation of the transmitter and the receiver. The error detection device applies at least one predetermined rule to the protocol signals, wherein a violation of the at least one rule by the protocol signals indicates that an error in the transmission of the packet has occurred, and asserts an error signal when the at least one rule has been violated by the protocol signals. The system further includes a packet filtering device coupled to receive the error signal from the error detection device and the data packet from the receiver, wherein, upon receiving the asserted error signal, the packet filtering device terminates the transmission of the data packet to the destination device.

Abstract: Systems and methods for storage area network switch port failure recovery. A system may include several hosts, storage devices and a storage area network (SAN) switch. The SAN switch may include several ports, where each host is coupled to a respective host port and each storage device is coupled to a respective storage port. The SAN switch may also include virtualization logic configured to map several of the storage devices as a volume presented to the hosts via the respective host ports, and an input/output (I/O) tracking mechanism configured to store information about write operations in progress at each of the ports. In response to a failure of a given port occurring while write operation(s) to the volume received via one or more of the respective host ports are in progress, the SAN switch may be configured to initiate consistency recovery of the volume using the stored information.

Abstract: A method for executing a computer program on computing hardware, e.g., on a microprocessor, is provided, the computer program including multiple program objects and errors being detected in this method while the computer program is running on the computing hardware. When an error is detected, at least one program object, which has already been sent for execution, is transferred into a defined state and is restarted from there, and subsequent additional program objects are shifted.

Abstract: A medium storage apparatus writes data for stream type commands on a medium, and improves the reliability of the write data while maintaining the execution time of the commands. The apparatus has a buffer for storing the write data of the write stream type commands, a controller for sequentially writing the data of the buffer to the medium by a head, and a processing unit for skipping the writing of erred sectors for continuing the processing which normally ends if an error occurs, and writing the data to the skipped sector after command execution. By this, the error is corrected such that the medium is correctly read in the next and later read processing, while maintaining the write time specified by the command.

Abstract: In one embodiment, a method is contemplated. The method includes creating a copy of a volume, wherein the copy corresponds to a first point in time. Write operations to the volume are logged separate from the volume. The method also includes recovering a state of the volume to a second point in time subsequent to the first point in time using the copy of the volume from the first point in time and at least a subset of the write operations from the log. The subset of write operations occurs subsequent to the first point in time and prior to the second point in time. In some embodiments, an end marker may be included in the log, and recovery to a write operation that is indicated as the end of a transaction (by the end marker) may be performed.

Abstract: The present invention provides a method for handling reordered data packets. A method comprises receiving a data packet and determining if the data packet is received out of order. The method further comprises delaying transmission of an acknowledgement indicating that a data packet is missing in response to determining that the data packet is received out of order.

Abstract: Described is a revert preview mechanism, which gives the user a chance to temporarily remount a storage volume with the contents of a shadow copy, and then evaluate the computer system as if reverted, including allowing full I/O read and write operations to the storage volume. A temporary storage location is provided to cache data writes. Read requests are read back from the temporary storage location if the corresponding volume location has been written, or are read back from the shadow copy of the volume if not written since the revert preview operation began. In the case of a revert preview of the boot volume, an API is used to specify a correct shadow copy instance of the system registry hive, which needs to be loaded following reboot, but before the shadow copy driver is loaded. Use of the API loads the correct instance on the next reboot.

Abstract: A processing system includes multiple processing units. After multiple event handlers have been dispatched to execute concurrently in different processing units of the processing system in a hidden execution mode, the processing system automatically determines whether the multiple event handlers successfully complete. If an event handler among the multiple dispatched event handlers fails, the processing system automatically dispatches another event handler to perform operations associated with the event handler that failed. In an embodiment, the hidden execution mode is a system management mode (SMM), and the multiple event handlers are dispatched in response to a system management interrupt (SMI) or a platform management interrupt (PMI). In an embodiment, the processing system may determine why the dispatched event handler failed, and may performing a corrective operation before dispatching another event handler to perform the operations associated with the event handler that failed.

Abstract: A storage control apparatus of the present invention reduces the frequency of disk drive failures. An error management part manages the number of times errors occur in respective disk drives. A disk drive in which the number of errors meets or exceeds a threshold value is selected as a disk drive to be restarted. A restart control part commences difference management prior to restarting the disk drive targeted for restart. A difference management part manages parity group-related update locations using a difference bitmap. After commencing difference management, the restart control part restarts the disk drive in which the error was detected. This makes it possible to resolve an error caused by a firmware hangup or the like.

Abstract: An error-handling framework is provided for business process transactions. The error-handling framework facilitates coordination of the invocation of exception and compensation handlers in response to errors. The error-handling framework includes support for custom ordering of compensation actions, data flow into and out of compensation actions, and management of the process state visible to compensation actions.

Abstract: A method and an apparatus to perform fast log replay have been disclosed. In one embodiment, the method includes preloading a buffer with data based on a catalog in response to a failure of a storage server and replaying a log as the buffer is being preloaded, wherein replaying the log comprises re-executing a set of modifying operations previously logged in a local non-volatile storage device in the storage server using the data preloaded.

Abstract: A command is received, at a network storage driver, from an operating system storage stack, wherein the command is for communication with a target storage device over a connection across a network. The command is selectively executed, a plurality of times over the connection, for communicating with the target storage device, in response to a determination that the command failed to successfully communicate with the target storage device within a threshold period of time.

Abstract: A method, system, and computer program product for generating checkpoint information in a database management system that determines the frequency of checkpointing of transactions based on a cost/benefit tradeoff analysis. A method for generating checkpointing information in a database management system comprises the steps of generating redo information based on transactions processed by the database management system, determining a cost of recovery using the redo information, determining a cost of taking a checkpoint, receiving a user specification of acceptable recovery delay and acceptable checkpoint overhead, and taking a checkpoint when cost effective to do so based on the cost of recovery using the redo information, the cost of taking the checkpoint and the user-specified acceptable delay and overhead.

Abstract: Whenever a DSLAM or a network node receives a Group Join message, it compares the MAC address of the originating STB to that of previous Join messages with their existing connections. If a match is found, then the DSLAM will initiate a GSQ for the group of the matching previous Join request. If there is not enough resources to satisfy the requirements of Group Join messages, then it may either be ignored, or queued for later processing, once the normal GSQ sequence is complete and resources are available. If the multicast group is no longer needed, the connection to the group is then terminated, as per normal GSQ processing. This frees up bandwidth for any new Join messages. The normal GSQ processing clears the trouble caused by the loss of Leave Message.

Abstract: An apparatus and method for maintaining integrity of data in a software environment are provided. With the apparatus and method, the individual software resources associated with a transaction are identified and the processing of these resources is started. As the processing of these resources terminates, their associated APIs return messages indicating either that the software resource committed or was unable to commit and the reason why the software resource was unable to commit. Based on this reason, appropriate error resolution and recovery operations are performed and the transaction is resubmitted only to those software resources that were unable to commit. The software resources that already committed have their states maintained. In this way, roll back of committed software resources is avoided.

Abstract: The invention relates to a process for implementation of a redundant switched full-duplex Ethernet type communication network comprising at least two independent elementary networks, each elementary network (RE1, RE2) comprising at least one source subscriber equipment and at least one destination subscriber equipment, connected to each other through at least one physical link through at least one switch, each equipment being connected to each of these elementary networks (RE1, RE2) in which a frame by frame redundancy is made on each elementary network.

Abstract: A DBMS performs a checkpoint process for maintaining consistency of data. A snapshot acquisition control program detects the checkpoint process externally to the DBMS and creates a snapshot in an external storage according to the timing of the checkpoint. Correspondence between checkpoints and snapshots is maintained in a CP-SH correspondence management table to make it possible to restore in a short time data at the time of an arbitrary checkpoint.

Abstract: A method for managing computer memory, in accordance with the present invention, includes maintaining multiple sets of free blocks of memory wherein a free block is added to a set based on its size. In response to a request for a block of a request size, a set of blocks is searched for a free block which is at least as large as the request size but smaller than the request size plus a threshold. If such a block is found, the block is allocated in its entirety.

Abstract: A method and apparatus is provided for processing tasks with failure recovery. The method includes storing one or more tasks in a queue, wherein each task has an associated exit routine, and determining at least one task to process based on a priority scheme. The method further includes processing the at least one task, and calling the exit routine based on determining that the task has not completed processing within a preselected period of time.