Abstract: A log acquisition method is provided that allows a processing log of software to readily be acquired and reduces the man-hours needed for analyzing a bug. The log acquisition method is a method for acquiring a runtime log of a program including a function, comprising the step of changing the address of the function loaded to the address of a function for log acquisition and selecting the function, wherein the function for log acquisition comprises the steps of: calling the function the log of which is to be acquired to cause a predetermined process to be executed, receiving the result of the execution, and passing said result to said program, recording given information when calling the address of the selected function, and recording given information when receiving the result of the execution of the selected function.

Abstract: A checkpointing method and system that utilize a write back controller. The system can include a first controller for implementing a first function, wherein the first function comprises part of a checkpoint operation and wherein the checkpoint operation comprises a series of contiguous checkpoint cycles. The system can also include a second controller, the second controller for implementing a second function, wherein the second function comprises a write back operation from a first memory location to a second memory location and wherein the write back operation occurs before a checkpoint cycle ends. Information already at the second memory location can be selectively written back to a third memory location.

Abstract: A log list comprising log identifiers is received, wherein the log list delineates a set of logs to be groomed. A log sequence number and a time-stamp are extracted from the first log record of each log in the set of logs. A system ID is extracted from a log record of each log in the set of logs. An appended log list is created wherein the system ID, time-stamp and log sequence number comprise appended information that is logically appended to each of respective ones of the log identifiers. The appended log list is sorted utilizing at least a portion of the appended information, the result comprising a sorted appended log list. An actual log sequence number is extracted from the last log record of each log in the set of logs. Each of the actual log sequence numbers is compared to a corresponding predicted log sequence number, wherein the corresponding predicted log sequence number is computed utilizing the sorted appended log list.

Abstract: Methods for updating an electronic device having a non-volatile memory are disclosed. An embodiment of the present invention may permit the update of an electronic device from a first code version to a second code version using a fault-tolerant, bank-by-bank method. An update package comprising update instructions may be received via a public and/or wireless network, and the update instructions may be used to convert the first code version to the second code version. The bank order of the conversion may be specified in the update package, and may be non-sequential.

Abstract: Bulk data is read or written by an application on a first computer system to a file on a second heterogeneous computer system. Alternatively it is read or written as bulk data directly between applications on these heterogeneous systems. Jobs or tasks are started from one system to execute on a second heterogeneous system. Results are then returned to the first system. Checkpointing and later restarting is also initiated from a first system for execution on the second heterogeneous system.

Abstract: Two data centers located in the vicinity are connected using a synchronous transfer copy function, and one of the data centers is coupled with a third data center disposed at a remote location by an asynchronous remote copying function. The order whereat a storage sub-system located in the vicinity has received data from a host is consistently guaranteed, and the third data center holds the data. Further, each storage sub-system includes a function whereby, during normal operation, data can be exchanged and the data update state can be obtained by the storage sub-systems located in the two data centers that do not directly engage in data transmission.

Abstract: The present invention reconstructs and illustrates incomplete change records by initially selecting an initial change record. The initial change record describes a change made to a target data object located at a target location in an electronic database. Next, a transaction log associated with the electronic database is searched for change records which modify the target data object. Eventually, a particular change record is located which contains a complete copy of the data object. Finally, the change records are applied to the complete copy of the data object, thereby bringing the complete copy of the target data object to a state as it existed before the change described by the initial change record was made to the target data object.

Abstract: Nodes in a distributed system maintain virtual times according to specified rules. Each node can associate its virtual time with transactional messages that are transferred to other nodes and with log entries that are written to a log. A reference entry, which corresponds to an arbitrary point in time, is selected from a first log associated with a first node. A reference virtual time associated with the reference entry is identified. A matching entry, with an associated virtual time that appropriately corresponds to the reference virtual time, is selected from a second log associated with a second node. The first node is caused to roll-forward to the arbitrary time by processing the first log up to the reference entry. The second node is caused to roll-forward to the arbitrary time by processing the second log up to the matching entry.

Abstract: A method, system, and computer program product that enable integrated scheduling and management of frozen images for backup and recovery purposes. Frozen images are created, cataloged, and managed in accordance with a backup policy including a schedule for generating frozen images. Minimal data are saved to allow fast synchronization of the persistent frozen images with production data, and frozen images are cataloged in a catalog that may include entries for other types of backups to provide a single source of information for all backups of production data.

Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.

Abstract: This invention describes a high-performance, log-structured implementation of a RAID subsystem that can be efficiently implemented in software. The methods described in this invention are extraordinarily well suited for software-based RAID 5 systems. In one embodiment, the disk storage subsystems receiving a request to write data. Thereafter, the write operation is appended to a first log to identify a storage location of data written to the disk subsystem, wherein the first log consists of a sequence of segments, the segments consist of a sequence of variable length stripes, a length of a stripe varies based on a quantity of disks addressed by a stripe. In response to adding a disk to the disk storage subsystem, increasing a length of the stripes and increasing a number of disks available for striping data. Alternatively, in response to a disk failing within the disk storage subsystem or a disk being removed from the disk storage system, narrowing a length of the stripes.

Abstract: There is described a method of maintaining a record of changes to data on a recording medium and allowing reconstruction of the state of the medium at a prior time.

Abstract: A clock distribution architecture having clock and power failure protection is disclosed. In one embodiment, a computer system includes a plurality of client boards and a plurality of switch boards, as well as having power distribution boards and clock boards (referred to herein as service processor boards). In one embodiment may include a clock board and a plurality of power distribution boards, while another embodiment may include a power distribution board and a plurality of clock boards. The clock board(s) may generate a global clock signal, which may be distributed to the switch boards and the power distribution board(s). The power distribution board(s) may distribute the global clock signal to the client boards. Clock redundancy may be provide through either having multiple clock boards or multiple power distribution boards.

Abstract: A remote site stores data received from a currently-used site and transfers the stored data to a proximal site. The proximal site stores the data received from the remote site and transfers the stored data to the currently-used site. The currently-used site crosschecks the data returned from the proximal site against the data transmitted to the remote site, and when the two data do not match each other, transmits the data to the remote site again.

Abstract: An improved method, mechanism, and system for implementing, generating, and maintaining records, such as redo records and redo logs in a database system, are disclosed. Multiple sets of records may be created and combined into a partially ordered (or non-ordered) group of records, which are later collectively ordered or sorted as needed to create an fully ordered set of records. With respect to a database system, redo generation bottleneck is minimized by providing multiple in-memory redo buffers that are available to hold redo records generated by multiple threads of execution. When the in-memory redo buffers are written to a persistent storage medium, no specific ordering needs to be specified with respect to the redo records from the different in-memory redo buffers. While the collective group of records may not be ordered, the written-out redo records may be partially ordered based upon the ordered redo records from within individual in-memory redo buffers.

Abstract: The present invention is directed toward a data management appliance and ancillary technologies for replicating data written to a primary storage system. The data management appliance is a random-access storage system that at the logical block level replicates the contents of a primary storage system over time.

Abstract: A system, and a method, for reorganizing an execution schedule. According to the invention, the recovery time of a storage device where a failure occurs is determined. Then, according to the recovery time, a schedule is produced for the operations that use the storage device where the failure occurred, and for the operations that do not use the storage device.

Abstract: In order to reproduce the past operations of a medical system, a reproduction test service apparatus stores a plurality of past log files directly or indirectly supplied from the medical system in a log file storage unit and reproduces the past operations of the medical system on a pseudo X-ray CT system in accordance with the stored log files.

Abstract: Methods and systems for managing disk capacity allocated to a data log in a source data storage system during a merge process are disclosed. Data in the data log may be merged into corresponding data on a destination storage system connected to the source data storage system by at least one communication link. In one embodiment a method comprises maintaining a ratio of merge writes out of the data log to writes from a host computer into the data log within a desired range until the write process reaches a predetermined distance from the end of the data log, and quiescing writes from a host computer into the data log until the data log is fully written to the destination storage system.

Abstract: There are provided a mainframe 1 constituting a host device and a disk array system 2 having logical volumes (LDEV) 30 connected with the mainframe 1. The mainframe 1 is provided with an input/output device configuration definition information storage section 14 that stores the address of an LDEV 30a. By referring to the input/output device configuration definition information storage section 14, a command is then issued giving an instruction to perform back-up of the LDEV 30a specifying the address of the LDEV 30a. The disk array system 2 receives the back-up command, specifies the generation to which the LDEV 30a is to be backed up and backs up to an LDEV 30b to 30d corresponding to the specified generation.

Abstract: Setting a plurality of table entries in a storage device includes subdividing the table entries into a N tasks, placing each of the N tasks in a memory location disposed within the storage device and accessible by a plurality of internal devices, the plurality of the internal devices accessing the memory location to retrieve at least one of the N tasks, and each of the plurality of the internal devices setting table entries corresponding to at least one of the N tasks retrieved from the memory location. Setting table entries may also include setting logical device table entries to indicate corresponding tracks contain invalid data in connection with operation of remote data transfer between multiple storage devices.

Abstract: The invention provides a method for error detection of multi-threaded software. The method comprises executing an application which uses a logger that collects log statements, collecting at least one log statement from at least one application thread and storing the at least one log statement in memory, and allowing the collected log statement to be persisted in case of an error in a production environment.

Abstract: The present invention relates to a power failure recovery mechanism for a recording and reproducing device such as a DVD player, wherein a recording indication information and a recovery pointer information is written in a non-volatile random access memory, while a recovery information is recorded on a record carrier such as a recordable optical disc. At a power-up operation, the recording indication information is used to determine a power failure and the pointer information is used to reproduce the recovery information in case of a determined power failure. Thus, the pointer information indicates the location of incremental recovery data structures on the record carrier, such that a recovery can be achieved after a power failure without requiring a restart of the entire recording.

Abstract: A method for data journaling includes writing data into at least one block in a journal storage area, and marking each written block as dirty. If the number of blocks in the journal storage area marked as dirty is greater than the number of blocks in a corresponding data storage area that have been used and whose corresponding blocks in the journal storage area are not marked as dirty, then those used blocks are copied to the corresponding blocks in the journal storage area, and a message is transmitted instructing a meta-data server to swap the data storage area and the journal storage area. If this condition is not so, the blocks in the journal storage area marked as dirty are copied to corresponding blocks in the data storage area, and a message is transmitted instructing the meta-data server to commit the data stored in the journal storage area.

Abstract: A reception apparatus records a content distributed from a content distribution apparatus on a hard disk. Following an instruction from a viewer, the reception apparatus reproduces the content. The reception apparatus transmits management information including identification information about the content recorded on the hard disk to a management apparatus. The management apparatus stores the information in a management information storage. When the hard disk of the reception apparatus fails, a replacement hard disk is attached to the management apparatus. The management apparatus retrieves, based on the stored management information, the same content as the content recorded on the hard disk of the reception apparatus from a content distribution apparatus, etc., and records the retrieved content on the replacement hard disk. The hard disk of the reception apparatus is then replaced with the replacement hard disk with the content recorded thereon.

Abstract: Disclosed is a technique for applying changes back to an original copy of data to reduce an amount of data transferred. A first indicator is maintained for each block of data in a first storage to indicate whether the block of data has been updated in the first storage since the block of data was last transferred to a second storage. A second indicator is maintained for each block of data in the second storage to indicate whether the block of data has been updated in the second storage since the block of data in the second storage was overwritten by a corresponding block of data in the first storage.

Abstract: A method is provided for checking a computer system configuration in which a first check file is provided (28). A second check file is compiled (34) from the computer system configuration. The first and second check files are compared against each other (36) and a computer system configuration is approved (38) in dependence on the result of this comparison. This process can take place at the point of manufacture or at a customer installation or both.

Abstract: A method and system for processing multi-agent cooperative transactions. A failure detector is provided for detecting whether a failure is an intra-enterprise failure or an inter-enterprise failure. An intra-enterprise failure handler is coupled to the failure detector for performing failure recovery for intra-enterprise failures. Failure recovery for intra-enterprise failures can include identifying the scope of failure recovery within a first enterprise. Once the scope of failure recovery has been identified, a top-down undo operation of sub-transactions in the identified scope may be performed within the first enterprise. An inter-enterprise failure handler is also coupled to the failure detector for performing failure recovery for inter-enterprise failures. Failure recovery for inter-enterprise failures can include identifying the scope of failure recovery in a second enterprise to which a failure in a first enterprise has been transfered.

Abstract: A method for disaster recovery includes copying at least a portion of information from a first database to a backup system as backup information. The method also includes storing an incremental change in a second database. The incremental change represents a change to at least a portion of the information in the first database. The method further includes restoring the first database using at least one of the backup information and the incremental change.

Abstract: A computer system has a plurality of sub-systems each comprising a serial interface and a buffer device coupled with the serial interface for buffering crash data sent by the serial interface having an external serial output. The system further comprises a management controller coupled with the external serial output of the buffer device to retrieve data buffered during a crash.

Abstract: Systems, methods and software products are provided for transaction logging and intelligent error reporting in an expectation-based memory agent checker. Simulation status information is appended to one or more transaction log messages generated by the expectation-based memory agent checker. A cause of error indicated by mismatch between simulated output transaction events and expected output transaction events is determined. Information about the error is appended to one or more error messages generated by the expectation-based memory agent checker.

Abstract: Lossless, context-free data compression is implemented using a data aware compression scheme that is specific to the type of data being compressed. A modified delta compression scheme is used in which difference information is encoded with reference to a set of typical difference values that commonly occur for the type of data being compressed. Selecting the compression scheme based on the type of data being compressed allows highly-compressed, yet lossless, compression. In addition, the contextual information required to uncompress information is reduced or eliminated, thereby enabling random access of the compressed data.

Abstract: If an incidental interruption of power supply occurs in a system, an apparatus and method is provided that a status immediately before the interruption of power supply can be stored. A request for a status-storing process is outputted from an application to a check point manager in a module. A request for an execution of a snap shot output to components, such as the application, a device driver and the like, is outputted to the manager. A sequence at this time is based on an sequence recorded in a status-storing database. The sequence represents a dependence relation between the components. When each component receives the request for the snap shot output, a function existing in a particular address for each component is read out and the component status is outputted as a snap shot file through the manager to a non-volatile memory.

Abstract: A data storage system maintains a production dataset supported by a clone volume, and multiple snapshot datasets supported by respective save volumes in a snapshot queue. In order to instantaneously restore the production dataset with the state of any specified snapshot, the data storage system responds to requests for read/write access to the production dataset by reading from the specified snapshot dataset and writing to the production dataset. The data storage system keeps a record of data blocks that have been modified by writing to the production dataset. The data storage system initiates a process of copying data blocks from the specified snapshot dataset to the production dataset if the record of the data blocks indicates that the data blocks have not yet been modified by writing to the production dataset.

Abstract: A unique comment keyword is given to a comment statement in a source code. If the comment statements are insufficient, a comment including the comment keyword is inserted in this insufficient part thereof. After this processing, the comment statements are extracted from the source code to create specification data. The specification data is displayed on a display 15. An operator completes the specification data by editing. The comment statement in the source code is replaced with the comment statement in the complete specification data based on the comment keyword being used as a key.

Abstract: A method for remote backup includes: mirroring data from a primary storage device at a first location to a secondary storage device at a second location; taking a snapshot of the primary storage device and of the secondary storage device; storing the primary storage device snapshot on a first snapshot volume at the first location; storing the secondary storage device snapshot on a second snapshot volume at the second location; updating a data structure to record backup times for the first and second snapshots and to record locations of the snapshots on the snapshot volumes; and repeating the above so as to store multiple generations of snapshots. A method for fast restore uses a selected snapshot located at the first location to restore data. If the selected snapshot at the first location is not available, the selected snapshot at the second location is used.

Abstract: A backup method for the basic input/output system (BIOS) of computer interfaces is disclosed. When the BIOS of an interface is broken, the backup BIOS stored in the computer can be transferred to the interface for maintaining normal operations.

Abstract: Setting a plurality of table entries in a storage device includes subdividing the table entries into a N tasks, placing each of the N tasks in a memory location disposed within the storage device and accessible by a plurality of internal devices, the plurality of the internal devices accessing the memory location to retrieve at least one of the N tasks, and each of the plurality of the internal devices setting table entries corresponding to at least one of the N tasks retrieved from the memory location. Setting table entries may also include setting logical device table entries to indicate corresponding tracks contain invalid data in connection with operation of remote data transfer between multiple storage devices.

Abstract: A file server maintains a production file system supported by a clone volume, and multiple snapshot file systems supported by respective save volumes in a snapshot queue. Before a data block is modified for the first time after creation of the youngest snapshot, the data block is copied from the clone volume to the save volume of the youngest snapshot. A bit map indicates the blocks that have already been copied, and a block map shows the save block address for each corresponding clone block address. When a new snapshot is created, the bit and block maps are converted to a hash index that is kept linked to the save volume of what had been the youngest snapshot. When other than the oldest snapshot file system is deleted, the respective save volume is retained as a hidden object until it becomes the oldest save volume.

Abstract: An electronic control system has a plurality of mutually networked or communicating control units, with special, redundant safeguarding measures during transmission of a safety-related transmitted signal from a first control unit to a second control unit. The first control unit generates the transmitted signal and a second signal complementary thereto on different paths, and sends them to a memory, together with two additional signals which are significant for the paths. A third control unit reads out the transmitted signal and the second signal from the memory, and checks them, and, upon detection of an error, switches off the first control unit or, given correct signals, generates different types of test or safety signals and conducts them to a memory.

Abstract: A data storage system adapted to maintain redundant data storage sets at a destination location(s) is disclosed. The data storage system establishes a copy set comprising a source volume and a destination volume. Data written to a source volume is automatically copied to the destination volume. The data storage system maintains a data log that may be activated when the destination volume is inaccessible due to, for example, a malfunction in the destination storage system or in the communication link between the source system and the destination system. I/O commands and the data associated with those commands are written to the data log, and after a destination system becomes available the information in the data log is merged into the destination volume to conform the data in the destination volume to the data in the source volume. The data log competes for disk capacity with other volumes on the system, and log memory is allocated as needed.

Abstract: Methods and systems to minimize the number of messages transmitted between a client and a server in a client-server network. The messages may be error messages, and may be associated with a log such as an error log. The client requests permission of the server to transmit a message(s) to the server. Upon receipt of the request, the server provides the client with a filter, which may include a filter table with a filter parameter(s). The server may provide the filter in real time and/or without the client or server having to go off-line. The client uses the filter to filter at least a selected message from the message(s). Once the client has filtered the selected message the client transmits the selected message and/or the associated log of the selected message to the server.

Abstract: In an enterprise-wide network which includes at least one centralized computer and a plurality of desktop computers, a method for enterprise system management comprising the steps of: storing an Already Have list for each desktop; storing a plurality of Should Have sub-lists; and generating a respective Should Have list from the stored sub-lists for a respective desktop computer during configuration of the desktop computer; wherein the Schema of the generated Should Have list includes at least one dynamic linkage which encompasses more than on Should Have sub-lists.

Abstract: Failure prediction for complex processes is performed utilizing one or more nonlinear regression models to relate operational variable values measured at two or more times to predicted process metric values and maintenance variable values.

Abstract: A system and method that uses a process management console to maintain multiple processes that perform software services from within a presentation layer and a database layer. The method includes defining an active process list for a plurality of processes that provide services in the presentation and database layers. Another step is monitoring the plurality of processes that are active in the presentation and database layers by using a process monitor. The next step is determining when one of the processes has abnormally terminated, using the process monitor to periodically compare the active process list to the list of processes currently executing. When a process fails, the system reactivates the process under the automatic control of the process monitor, and the reactivation is performed automatically. The system can also generate an error message that is logged or sent as an email to support personnel when a process has failed.

Abstract: The present invention provides a method for keeping a file system in a consistent state and for creating read-only copies of a file system. Changes to the file system are tightly controlled. The file system progresses from one self-consistent state to another self-consistent state. The set of self-consistent blocks on disk that is rooted by the root inode is referred to as a consistency point. To implement consistency points, new data is written to unallocated blocks on disk. A new consistency point occurs when the fsinfo block is updated by writing a new root inode for the inode file into it. Thus, as long as the root inode is not updated, the state of the file system represented on disk does not change. The present invention also creates snapshots that are read-only copies of the file system. A snapshot uses no disk space when it is initially created. It is designed so that many different snapshots can be created for the same file system.

Abstract: A method of maintaining a hierarchy of application objects commences with the automatic detection of the exit of a process of a child application object in an unexpected manner. Responsive to the detected exit, a grandchild application object, launched by the child application object, is automatically terminated. An attempt is then made to restart the child application object. The outcome of the restart of the child application object is reported to a parent application object that launched the child application object.

Abstract: A method or system for supporting a computer systems self repair, including the computer executed steps for booting from a first boot device, and booting from a second boot device in response to a signal indicating a need for repair. While booted from the second boot device the computer system is capable of repairing software on the first boot device. The signal may effect a logical or physical switch. Repairing software may be performed in part by copying BIOS, template, backup or archive software from a device other than the first boot device. Repairing software may be performed automatically without direction by a user or according to preset preferences.

Abstract: A method, apparatus, article of manufacture, and data structure for use in providing transaction control for a computer-implemented database management system. The database management system manages one or more databases. A transaction processing system provides transaction control for one or more of the databases managed by the database management system, wherein the transaction processing system assigns a recoverable, unique sequence number whenever a request is made by an application.

Abstract: A process data capture and reporting system captures process data values at sensors. A client computer appends absolute-value time stamps to the values to complete records, which are uploaded to a server. The server writes the records to a persistent database. At a later stage, the server retrieves selected records, and performs a very fast conversion of the time stamps to a calendar format with “granular” values for units such as day, month, or minute. The conversion is performed in an optimised manner with use of look-up tables in memory. This minimises processor overhead, and is thus very advantageous where data volumes are high and/or near real time reporting is required.