Abstract: A periodic rotational vibration check for storage devices to compensate for varying loads is disclosed. A variable representing rotational vibration status is maintained in a rotational vibration log. The variable is processed to determine whether a storage device exhibits a rotational vibration issue. Workload analysis is performed to identify a change to the workloads run on physically separate hardware to resolve the rotational vibration issue and thus eliminate the need for more expensive hardware.

Abstract: A method and controller for implementing storage adapter performance control, and a design structure on which the subject controller circuit resides are provided. The controller includes a performance state machine controlling the use of a performance path and a normal or error recovery path in a storage adapter firmware stack. The performance state machine determines which storage resources are allowed to use the performance path and properly transitions the running of each storage resource to and from the performance path and normal path mode of operation.

Abstract: Aspects of the subject matter described herein relate to querying and repairing data. In aspects, a component may detect that data on storage has become corrupted. In response, the component may request data from one or more redundant copies of the data and may determine which of the redundant copies, if any, are not corrupted. If a non-corrupted copy is found, the component may send a request that the corrupted data be repaired and may identify the non-corrupted copy to use to repair the corrupted data.

Abstract: Systems and methods to implement a multi-level memory system having a volatile memory and a non-volatile memory are implemented. A home agent may control memory access to both a volatile main memory and a non-volatile second level memory. The second level memory may be inclusive of the main memory. In an embodiment, the home agent may be configured to manage the memory system in a low power state. In a low power state, the volatile memory may be shut down and the non-volatile memory utilized as the only local memory. In an embodiment, the home agent may be configured to manage error recovery for the main memory by recovering the data saved locally in the second level memory. In an embodiment, multiple cores may access the second level memory.

Abstract: An apparatus including at least one memory controller; and a plurality of random access memories, where the at least one memory controller is configured to allocate the plurality of random access memories among at least a first portion, a second portion and a third portion. The first portion is configured to store protected data. The second portion is configured to store parity information for the stored protected data. The third portion is configured to store unprotected data.

Abstract: A method begins by a processing module receiving a large data file for storage in a dispersed storage network (DSN) and determining initial dispersed storage error encoding parameters. The method continues with the processing module encoding, during a first time interval of receiving the large data file, first data segments of the large data file using the initial dispersed storage error encoding parameters to produce a first plurality of sets of encoded data slices. The method continues with the processing module writing the first plurality of sets of encoded data slices to the DSN and monitoring processing of the writing to produce first write processing performance information. When the first write processing performance information compares unfavorably to a desired write performance range, the method continues with the processing module adjusting, for a second time interval, the initial dispersed storage error encoding parameters to produce adjusted dispersed storage error encoding parameters.

Abstract: Techniques for implementing memory sparing with a memory controller. In an embodiment, a memory controller stores memory sparing information which is specific to a first line of memory in a memory coupled to and controller by the memory controller. In another embodiment, the memory controller includes a second memory line which is to operate as a spare for the first line of memory, where accessing the second memory line is to be a substitute for accessing the first memory line.

Abstract: Processing for file system volume error detection and processing for resultant error correction are separated to support system availability and user satisfaction. File system volumes for storing data structures are proactively scanned while the volumes remain online to search for errors or corruptions thereon. Found errors are scheduled to be corrected, i.e., spot corrected, dependent on the severity of the identified errors, error correction scheduling and/or at the determination of a file system administrator and/or user, to assist in maintaining minimal user and file system impact. When spot correction is initialized, one file system volume at a time is taken offline for correction. Spot correction verifies prior logged corruptions for the offline volume, and if independently verified, attempts to correct the prior noted corruptions. Volumes are retained offline only for the time necessary to verify and attempt to correct prior noted volume corruptions.

Abstract: A method and controller for implementing storage adapter performance optimization with a predefined chain of hardware operations configured to minimize hardware and firmware interactions and a bridge code configured to select a firmware sequence for error recovery to complete the operations responsive to an identified error in the predefined chain, and a design structure on which the subject controller circuit resides are provided. A selected predefined chain is configured to implement a particular performance path to maximize performance. Responsive to an identified predefined error during hardware operations in the predefined hardware chain, a bridge code is configured to select a non-performance path firmware sequence for error recovery completion of remaining operations.

Abstract: A data control device includes: a switch portion that has a plurality of first terminals on an upstream side, a plurality of second terminals on a downstream side, and a circuit portion that optionally switches a connection between the first terminals and the second terminals based on an external switching signal; and at least one control portion that has a first input/output portion on the upstream side and a second input/output portion on the downstream side, wherein the second input/output portion is connected to the first terminal of the switch portion and the first input/output portion is connected to the second terminal of the switch portion, and wherein the at least one control portion controls an input/output of data between the first input/output portion and the second input/output portion.

Abstract: Recovery of a failed storage device of a RAID array to a replacement storage device is improved by initiating recovery before failure of the storage device occurs. If failure occurs before completing the transfer of all information from the failed storage device to the replacement storage device, then the RAID controller identifies untransferred information to recreate the failed storage device at the replacement storage device by re-building only the untransferred information with a parity operation using information stored at the array.

Abstract: A set of storage devices coordinates selection of dispersed storage error encoding parameters for storing a stream of data and coordinates selection of encoded data storage devices and redundancy encoded data storage devices of the set of storage devices. The encoded data storage devices coordinates storage of a decode threshold amount of encoded data of the stream of data in accordance with the dispersed storage error encoding parameters. The encoded data storage devices send information regarding the decode threshold amount of encoded data to the redundancy encoded data storage devices. The redundancy encoded data storage devices generates redundancy encoded data based on the information regarding the decode threshold amount of encoded data and in accordance with the dispersed storage error encoding parameters. The redundancy encoded data storage devices store the redundancy encoded data to provide error encoded reliable storage of the stream of data.

Abstract: Examples are disclosed for facilitating recovery from failures associated with a storage array having a plurality of storage devices.

Abstract: A method and system of checkpointing single process application groups and multi-process application groups. In an exemplary embodiment, the method may include creating at least one full checkpoint for each application in an application group, and creating at least one incremental application checkpoint for each application in the application group. Further, each of the at least one incremental application checkpoint may be automatically merged against a corresponding full application checkpoint. Further, checkpointing may be synchronized across all applications in the application group. In the exemplary embodiment, each application may use both fork( ) and exec( ) in any combination.

Abstract: A computer system functions to dynamically assign the storage capacity to the host computer. If an event such as a failure occurs in the logical resources, the performance requirements of the virtual volumes must be guaranteed to the host computer. Accordingly, the computer system comprising a storage apparatus, wherein the storage apparatus detects the occurrence of an event in the logical resources, compares the performance of the logical resources where the event occurred with the performance of the virtual volumes and, in accordance with the result of the comparison, sets the correspondence relationship of the virtual volumes to the logical resources.

Abstract: Systems and methods are disclosed for storing the firmware and other data of a flash memory controller, such as using a RAID configuration across multiple flash memory devices or portions of a single memory device. In various embodiments, the firmware and other data used by a controller, and error correction information, such as parity information for RAID configuration, may be stored across multiple flash memory devices, multiple planes of a multi-plane flash memory device, or across multiple blocks or pages of a single flash memory device. The controller may detect the failure of a memory device or a portion thereof, and reconstruct the firmware and/or other data from the other memory devices or portions thereof.

Abstract: Disclosed is a method of detecting a product data error in a storage system. First and second vital product data (VPD) EEPROMs are read. Indicators of whether wither or both reads failed are received. Based on these indicators, the contents of the VPD EEPROMs may be compared. Based on a result of the comparing indicating a match, an arbitrary one of the VPD EEPROMS is used. Based on an indicator indicating an error with the first VPD EEPROM, the second VPD EEPROM is used.

Abstract: A blade server is capable of being mounted with a plurality of operation blades, a plurality of switch blades, and I/O blades. The operation blades have CPUs that emit packets for the I/O blades. The switch blades include a crossbar that selects two or more of the plurality of operation blades, comparators that compare two or more packets emitted by CPUs that the two or more operation blades selected by the crossbar are provided with, and a further crossbar that transfers the compared packets to the I/O blades based on comparison results of the comparators.

Abstract: A method includes monitoring a plurality of HyperSwap sessions between one or more storage systems located at a first location and one or more storage systems located at a second location, wherein at least one of the one or more storage systems located at the first location and at the second location are designated as a primary storage system. The method includes detecting an error event and freezing communications between the storage systems located at the first location and the second location in response to the error event. The method also includes designating either the first location or the second location as a preferred location and modifying the designation of all of storage systems at the preferred location to be primary storage systems in response to the error event.

Abstract: A distributed storage network generates a plurality of data segments from a data object and stores each of the plurality of data segments as a plurality of encoded data slices generated from an error encoding dispersal function. When the distributed storage network receives a modification request for the data object, it determines a size of the plurality of data segments of the data object from a segment size field and identifies one of the plurality of data segments requiring modification. The identified data segment is reconstructed from the plurality of encoded data slices and modified in accordance with the modification request.

Abstract: Embodiments of the disclosure relate to a system and method for replacing a failed node in a distributed data storage network. The network includes storage nodes storing source data amongst them in a redundant manner that is coded using one of minimum-storage, minimum-bandwidth or twin code techniques. On failure of a storage node, means of obtaining the data of the failed node from the existing nodes are described, under each of these coding techniques. This action is performed in a manner that requires a minimal amount of download. The storage space required in the nodes is also minimized.

Abstract: A duplicate-aware disk array (DADA) leaves duplicated content on the disk array largely unmodified, instead of removing duplicated content, and then uses these duplicates to improve system performance, reliability, and availability of the disk array. Several implementations disclosed herein are directed to the selection of one duplicate from among a plurality of duplicates to act as the proxy for the other duplicates found in the disk array. Certain implementations disclosed herein are directed to scrubbing latent sector errors (LSEs) on duplicate-aware disk arrays. Other implementations are directed to disk reconstruction/recovery on duplicate-aware disk arrays. Yet other implementations are directed to load balancing on duplicate-aware disk arrays.

Abstract: A method begins with a processing module sending a plurality of dispersed storage write commands to plurality of dispersed storage (DS) units for storing a plurality of encoded data slices. The method continues with the processing module receiving, within a time period, acknowledgements from at least some of the plurality of DS units to produce received acknowledgements. The method continues with the processing module determining whether a number of received acknowledgements compares favorably to a write threshold. The method continues with the processing module changing at least one of the write threshold and at least one of the plurality of DS units when the number of received acknowledgements does not compare favorably to the write threshold.

Abstract: A method begins by a processing module sending list digest requests to a set of dispersed storage (DS) units. The method continues with the processing module receiving list digest responses from at least some of the set of DS units and determining whether an inconsistency exists between first and second list digest responses of the list digest responses. The method continues with the processing module requesting at least a portion of each of the slice name information lists from first and second DS units of the set of DS units and identifying a slice name information error associated with the inconsistency based on the at least a portion of each of the slices name information lists of the first and second DS units when the inconsistency exists between first and second list digest responses of the list digest responses.

Abstract: A redundant array of independent nodes are networked together. Each node executes an instance of an application that provides object-based storage. The nodes are grouped into a plurality of systems each having multiple nodes. An object recovery method comprises: receiving, by a first system of the plurality of systems from a client application, a read request for an object, the object having been replicated to/from at least one second system among the plurality of systems; if the object of the read request is available in the first system, returning by the first system the object of the read request to the client application; and if the object of the read request is not available in the first system, performing a read from replica process by the first system to access a replica of the object from a second system among the plurality of systems and using the replica of the object to return the object of the read request to the client application.

Abstract: A method begins by a processing module forward error correction (FEC) encoding data to produce FEC encoded data and dividing the FEC encoded data into a set of FEC encoded words. The method continues with the processing module generating integrity information based on the data and generating a word name for an FEC encoded word of the set of FEC encoded words. The method continues with the processing module affiliating an address of allocated address space of a dispersed storage memory with the word name and storing the integrity information, the word name, and the address. The method continues with the processing module creating a write command to store the FEC encoded word at the address in the dispersed storage memory.

Abstract: A method begins by a dispersed storage (DS) processing module identifying an encoded data slice having an error, where a storage unit of a dispersed storage network (DSN) stores the encoded data slice. The method continues with the DS processing module sending a lock command to the storage unit. The method continues with the DS processing module determining resolution for the error of the encoded data slice, where the resolution includes one or more of: rebuilding the encoded data slice, issuing a set of delete requests to storage units of the DSN regarding a set of encoded data slices, issuing a set of undo write requests to the storage units of the DSN regarding the set of encoded data slices, and issuing a set of roll-back write requests to the storage units of the DSN regarding the set of encoded data slices.

Abstract: Embodiments include a method and system of dynamically allocatable memory error mitigation. In one embodiment, a system applies an error mitigation mechanism to one of multiple groups of memory units, wherein the one group is in active use during an error test of a second group of memory units. The system deactivates and tests the second group of memory units for errors. In response to detecting an error in a memory unit of the second group, the system applies, to the memory unit of the second group having the error, the error mitigation mechanism for active use. The system then activates the second group of memory units with the error mitigation mechanism applied to the memory unit of the second group having the error.

Abstract: Redundant “parity” RAID (5, 6, 50, 60) is a well-known technique for increasing data reliability beyond the failure rate of an individual storage device. In many implementations of redundant RAID, when a storage element is lost, a replacement or spare element is required to restore redundancy. A typical solid state storage device is over-provisioned with more storage media than is required to satisfy the specified user capacity. Embodiments of the present invention utilize the additional over-provisioned capacity and potentially modify the stripe size to restore RAID redundancy when a storage element or path (i.e., page, block, plane, die, channel, etc.) has failed. In some cases, this may also involve reducing the RAID stripe size.

Abstract: A method includes providing a persistent common view of data, services, and infrastructure functions accessible via one or more shared storage systems of a plurality of shared storage systems of a virtual shared storage system. The method includes applying different governance policies to two or more shared storage systems of the plurality of shared storage systems. The method includes restricting access to first content accessible via a first shared storage system of the plurality of shared storage systems based on a security level associated with a data consumer. The first content corresponds to at least one of first data, a first service, and a first infrastructure function.

Abstract: A method providing a persistent common view of data, services, and infrastructure functions accessible via a plurality of shared storage systems of a virtual shared storage system. The method includes applying different governance policies at two or more shared storage systems of the virtual shared storage system. The method includes transferring content from a particular shared storage system to a requesting device without using at least one of a server session, an application-to-server session, and an application session. The content corresponds to at least one of data, a service, and an infrastructure function provided via the particular shared storage system.

Abstract: A method includes providing a persistent common view of a virtual shared storage system. The virtual shared storage system includes a first shared storage system and a second shared storage system, and the persistent common view includes information associated with data and instructions stored at the first shared storage system and the second shared storage system. The method includes automatically updating the persistent common view to include third information associated with other data and other instructions stored at a third shared storage system in response to adding the third shared storage system to the virtual shared storage system.

Abstract: In one embodiment, an apparatus includes memory comprising a first portion in which data contained therein is mirrored and a second portion wherein data contained therein is not mirrored, a memory allocator for allocating the first portion of the memory to critical data and allocating the second portion of the memory to non-critical data, and a processor for mirroring the critical data and receiving an indication of a memory error. If the memory error occurs in the first portion of the memory, a mirrored copy of the critical data is used. If the memory error occurs in the second portion of the memory, the memory error is contained so that the apparatus can continue to operate programs using the memory not affected by the memory error.

Abstract: A storage apparatus for storing data includes a plurality of physical media provided with storage areas to store data, a storage group determining unit configured to determine, upon detecting a request to write new data to a virtual volume to be accessed, a storage group from which to allocate storage area by selecting a storage group from among a plurality of storage groups made up of the plurality of physical media, wherein the selected storage group is other than any storage groups that include a physical medium where a failure has occurred, and a storage area allocator configured to allocate storage area on the physical media existing within the storage group that was determined by the storage group determining unit to the virtual volume, the size of the storage area corresponds to the data size of the new data.

Abstract: A storage server stores data in a stripe of a parity group that includes a plurality of data storage devices to store data and a parity storage device to store parity information. The stripe includes a data block from each of the data storage devices and a parity block from the parity storage device. The storage server receives a data access request specifying a data block in the stripe, and a lost write detection module detects an error in the data block. The lost write detection module compares a first storage device signature stored in a metadata field associated with the data block to a second storage device signature stored in a global field of the data storage device containing the data block. If the first storage device signature matches the second storage device signature, the lost write detection module compares a consistency point count stored in the metadata field to a reconstructed consistency point count.

Abstract: Replicated instances in a database environment provide for automatic failover and recovery. A monitoring component can periodically communicate with a primary and a secondary replica for an instance, with each capable of residing in a separate data zone or geographic location to provide a level of reliability and availability. A database running on the primary instance can have information synchronously replicated to the secondary replica at a block level, such that the primary and secondary replicas are in sync. In the event that the monitoring component is not able to communicate with one of the replicas, the monitoring component can attempt to determine whether those replicas can communicate with each other, as well as whether the replicas have the same data generation version. Depending on the state information, the monitoring component can automatically perform a recovery operation, such as to failover to the secondary replica or perform secondary replica recovery.

Abstract: Systems and techniques for virtual device sharing. A failure of one of a plurality of memory devices corresponding to a first rank in a memory system is detected. The memory system has a plurality of ranks, each rank having a plurality of memory devices used to store a cache line. A portion of the cache line corresponding to the failed memory device is stored in a memory device in a second rank in the memory system and the remaining portion of the cache line in the first rank of the memory system.

Abstract: A system comprises at least two random access memory (RAM) elements arranged to store data redundantly. The system further comprises RAM routing logic comprising comparison logic operably coupled to the at least two RAM elements and arranged to compare redundant data read from the at least two RAM elements, and check and validation logic, independent of the RAM routing logic, operably coupled to the at least two RAM elements and arranged to additionally detect an error in the redundant data read from the at least two RAM elements and provide an error indication signal to the RAM routing logic in response thereto. The RAM routing logic further comprises selection logic arranged to dynamically select redundant data from one of the at least two RAM elements based on the comparison of the redundant data and the error indication signal.

Abstract: A system for managing distributed storage includes a collection of one or more compute sites that are connected and that perform a joint computation. A witness node is connected to the one or more compute sites. A membership service allows a change in collection membership, in response to a failure, to continue the joint computation without causing data inconsistency or corruption. If the membership service is unable to reach a decision on the change in collection membership in response to the failure, the witness node controls the decision on the change in collection membership to continue the joint computation. A distributed storage system provided by the system described herein may advantageously meet consistency guarantees and maximize data access even when individual compute sites and/or their interconnects fail.

Abstract: A printing system including plural devices can appropriately stop normally operating devices in a short time when a problem occurs in any one of the plural devices. The printing system has devices that execute processes for printing on printing paper, device control units that control the devices, and a central control unit that centrally controls the devices. When a problem is detected in one device, the central control unit sends, as a command for a process to be executed immediately, a stop device command for stopping the other device to the device control unit that controls the device in which a problem is not detected. The device control unit that receives the stop device command executes a process based on the stop device command with priority over processes based on other commands, and stops the device.

Abstract: A method begins by a processing module determining that a data storage request is a cloud data storage request. The method continues with the processing module determining at least one of a cloud storage access reliability indication and a cloud storage data reliability indication for the data storage request. The method continues with the processing module sending the data storage request and the at least one of cloud storage access reliability indication and cloud storage data reliability indication to a cloud storage system.

Abstract: A method begins by a processing sending access requests to a threshold number of storage units of a dispersed storage network (DSN) and receiving, from each of at least some of the threshold number of storage units, an access response or an error response. When one error response is received from a storage unit of the at least some of the threshold number of storage units in response to one of the access requests, the method continues with the processing module ascertaining a likely cause for an error corresponding to the error response. The method continues with the processing module determining, based on the likely cause for the error, whether to resend the one of the access requests to the storage unit, issue a modified access request to the storage unit, or send the one of the access requests to another storage unit.

Abstract: A storage controller changes a block size to carry out a shredding process. A data shredder uses a large block size BSZ1 set by a block size setting part to write shredding data in a storage area of a disk drive and erase data stored therein. An error arising during the writing operation of the shredding data is detected by an error detecting part. When the error is detected, the block size setting part sets the block size smaller by one stage than the initial block size to the data shredder. Every time the error arises, the block size used in the shredding process is diminished. Thus, the number of times of writings of the shredding data is reduced as much as possible to improve a processing speed and erase the data of a wide range as much as possible.

Abstract: Since the whole storage device is blocked according to the conventional data saving method when failure occurs to the storage device in a storage subsystem, so that when failure occurs to two storage devices at the same time within a same RAID group, double failure is caused and data loss occurs. In order to solve the problem, the present invention divides a storage device into storage areas of predetermined units, constructs RAID groups from two or more storage areas, and when failure occurs to the storage area, selects a data migration destination storage area from either the RAID group in which failure has occurred or the RAID group other than the RAID group in which failure has occurred, migrates the data stored in the storage area where failure has occurred to the selected data migration destination storage area, and blocks only the storage area where failure has occurred.

Abstract: Methods and apparatuses for enhanced protection of data stored in a FLASH memory system involve a controller capable of protecting data using page stripes and auxiliary protection stripes. The controller stores the data in a manner such that the pages making up each page stripe include a plurality of data pages and at least one data protection page and the pages making up each auxiliary protection stripe include a plurality of data pages and an auxiliary protection page. At least a plurality of data pages are within one page stripe and one auxiliary protection stripe such that each data page is protected both by a data protection page in the page stripe and an auxiliary protection page in the auxiliary protection stripe.

Abstract: A method for verifying integrity of data stored in dispersed storage memory begins by a processing module retrieving integrity information of the data that is stored as a set of forward error correction (FEC) encoded words in the dispersed storage memory and continues with the processing module receiving FEC encoded words of the set of FEC encoded words from the dispersed storage memory to produce received FEC encoded words and decoding a unique subset of the received FEC encoded words to produce recovered data. The method continues with the processing module generating recovered integrity information from the recovered data and comparing the recovered integrity information with the integrity information. The method continues with the processing module indicating that at least one of the received FEC encoded words of the unique subset of the received FEC encoded words is corrupt when the recovered integrity information compares unfavorably with the integrity information.

Abstract: A method begins by a processing module receiving a write request that includes a batch of encoded data slices and a corresponding batch of slice names, wherein the batch of encoded data slices includes encoded data slices that have slices names that have a common data object storage name, a common slice storage name, and a different data segment storage name. The method continues with the processing module determining whether a storage file exists based on the common data object storage name. The method continues with the processing module creating the storage file based on the common data object storage name when the storage file does not exist. The method continues with the processing module storing the batch of encoded data slices in the storage file based on the corresponding batch of slice names.

Abstract: A method for storing data. The method includes receiving a request to write data, determining that the storage mode for the data is mirrored mode, selecting a Redundant Array of Independent Devices (RAID) grid location in a RAID grid to write the data based on the storage mode, writing the data to memory, updating a data structure to indicate that the RAID grid location is filled, and determining a data grid is filled. Based on the determination, determining a first physical address and a second physical address in persistent storage corresponding to the RAID grid location; writing the data to a first physical location in the persistent storage corresponding to the first physical address and writing the data to a second physical location in the persistent storage corresponding to the second physical address, and writing the parity values associated with data grid to the persistent storage.

Abstract: For preventing data loss in storage systems, a detection is made that a storage device in a plurality of storage devices is experiencing a malfunction. The type of malfunction is determined. A SMART rebuilding technique, a normal building technique, a data migration technique, or a user data backup technique is selected to preserve the data in the storage device based on the determined type of the malfunction. The selected technique is performed on the storage device.

Abstract: A method to prevent data loss includes monitoring a vibration from a computer rack and, when the vibration is harmful to a hard disk drive in the computer rack, moving data in transition to the hard disk drive to another hard disk drive, spinning down the hard disk drive, and sending an alarm. The method further includes, after the vibration is no longer harmful to the hard disk drive, spinning up the hard disk drive, moving the data from the other hard disk drive to the hard disk drive, and clearing the alarm and adding an event to an alarm history.