Abstract: Methods, apparatus, systems and articles of manufacture to compress data are disclosed. An example apparatus includes a data slicer to split a dataset into a plurality of blocks of data; a data processor to select a first compression technique for a first block of the plurality of blocks of data based on first characteristics of the first block; and select a second compression technique for a second block of the plurality of blocks of data based on second characteristics of the second block; a first compressor to compress the first block using the first compression technique to generate a first compressed block of data; a second compressor to compress the second block using the second compression technique to generate a second compressed block of data; and a header generator to generate a first header identifying the first compression technique and a second header identifying the second compression technique.

Abstract: A processing system includes a primary processor and a co-processor. The primary processor is couplable to a memory subsystem having at least one memory and operating to execute system software employing memory address translations based on one or more page tables stored in the memory subsystem. The co-processor is likewise couplable to the memory subsystem and operates to perform iterations of a page table walk through one or more page tables maintained for the memory subsystem and to perform one or more page management operations on behalf of the system software based the iterations of the page table walk. The page management operations performed by the co-processor include analytic data aggregation, free list management and page allocation, page migration management, page table error detection, and the like.

Abstract: A method, an electronic device, and a computer program product for data management is disclosed. The method includes receiving a request for performing, on data, a first management operation related to a first storage device, the request indicating a type of the data. The method further includes determining a first service associated with the type of the data and enabling the first service to perform the first management operation on the data. Thus, resource consumption of a data manager at runtime may be substantially reduced, which saves resources to reduce operating cost of the data manager, and improves the user experience of users who use the data manager.

Abstract: Methods, systems, and devices for performing data migration operations using a memory system are described. The memory system may include a data migration component, such as a driver, for facilitating the transfer of data between a first memory device that may implement a first memory technology (e.g., having a relatively fast access speed) and a second memory device that may implement a second memory technology (e.g., having a relatively large capacity). The component may indicate the data migration operation to a second component (e.g., a controller) of the memory system. The second component may initiate the transfer of data between the first memory device and the second memory device based on the receiving the indication of the data migration operation. In some cases, the transfer of data between the first memory device and the second memory device may occur within the memory system without being transferred through a host device.

Abstract: A method and apparatus for managing buffering of data packets of a network card, a terminal and a storage medium are provided. The method includes: setting ring buffer queues, setting a length of each ring buffer queue, then setting a buffer pool formed by two ring buffer queues, and setting the two ring buffer queues in the buffer pool as a busy queue and an idle queue, respectively; a network card driver receiving data packets from a data link, classifying the data packets, sequentially buffering the classified data packets into the busy queue, and then sequentially mapping addresses of the buffered data packets in the busy queue into the idle queue; acquiring latest addresses of the buffered data packets in the busy queue; and the upper-layer application successively acquiring and processing the buffered data packets, and successively releasing the addresses of the processed buffered data packets in the busy queue.

Abstract: Dynamic configuration of storage volumes based on data usage metrics is provided. Data may be initially written to a relatively low-throughput storage volume that is managed according to a usage metric. For example, a burst balance metric may be monitored and, if it falls below a threshold or reduces at a rate exceeding a threshold, the system can dynamically change to writing data to a higher-throughput data storage volume. After a period of time and/or if performance criteria are satisfied, the system can dynamically change to writing data to a lower-throughput data storage volume.

Abstract: An apparatus includes at least one processing device configured to identify a logical storage volume stored across multiple storage nodes of a distributed storage system, and for each of a plurality of different portions of the logical storage volume, to send one or more locality determination commands to each of one or more of the storage nodes, a given such command requesting a corresponding one of the storage nodes to respond with an indication as to whether or not the portion of the logical storage volume is local to that storage node, and to receive from the one or more storage nodes responses to the one or more locality determination commands. The processing device is further configured to store locality information for the plurality of different portions of the logical storage volume based at least in part on the responses of the storage nodes to the locality determination commands.

Abstract: Storage redundancy may be resynchronized without determining a snapshot difference. A storage component (210) owning a volume (122) can maintain current and expected generation numbers (212, 214) based on modification requests received and modification requests that a backup component (220) acknowledges completing. The backup (220) can maintain current and expected generation numbers (222, 224) based on modification requests received and applied to a backup volume (124). If either component (210, 220) fails and later returns to service, differences between the owner's current and expected generation numbers (212, 214) and the backup's current and expected generation numbers (222, 224) indicate which modification requests may have been missed and need to be reconstructed to restore synchronization.

Abstract: Various embodiments described herein provide for using a prefetch buffer with a cache of a memory sub-system to store prefetched data (e.g., data prefetched from the cache), which can increase read access or sequential read access of the memory sub-system over that of traditional memory sub-systems.

Abstract: A semiconductor device includes a first chip, a plurality of second chips, and a plurality of first signal lines. The first chip is electrically connected to a terminal group that receives a first signal from a host. The second chips are electrically connected to the first chip and are capable of outputting respective ready/busy signals. The ready/busy signals can be transferred through the first signal lines. Each of the second chips is respectively connected to the first chip through a corresponding first signal line among the plurality of first signal lines.

Abstract: A memory system includes a memory device and a processing device, operatively coupled to the memory device. The processing device performs operations comprising: identifying an operating temperature of the memory device; determining that the operating temperature satisfies a temperature condition; modifying a scan frequency parameter for performing a scan operation on representative blocks of a set of blocks in the memory device; and performing the scan operation at a frequency identified by the scan frequency parameter.

Abstract: A method is for operating a nonvolatile dual in-line memory module (NVDIMM). The NVDIMM includes a dynamic random access memory (DRAM) and a nonvolatile memory (NVM) device, the DRAM including a first input/output (I/O) port and a second I/O port, and the second I/O port connected to the NVM device. The method includes receiving an externally supplied command signal denoting a read/write command and a transfer mode, driving a multiplexer to select at least one of the first and second I/O ports according to the transfer mode of the command signal, and reading or writing data according to the read/write command of the command signal in at least one of the DRAM and NVM device using the at least one of the first and second I/O ports selected by driving the multiplexer.

Abstract: A processing device in a host system monitors a data temperature of a plurality of memory pages stored in a host-addressable region of a cache memory component operatively coupled with the host system. The processing device determines that a first memory page of the plurality of memory pages satisfies a first threshold criterion pertaining to the data temperature of the first memory page and sends a first migration command indicating the first memory page to a direct memory access (DMA) engine executing on a memory-mapped storage component operatively coupled with the cache memory component and with the memory-mapped storage component via a peripheral component interconnect express (PCIe) bus. The first migration command causes the DMA engine to initiate a first DMA transfer of the first memory page from the cache memory component to a host-addressable region of the memory-mapped storage component.

Abstract: A geographically distributed erasure coding system includes multiple computer readable, non-transitory storage memories capable of storing a digital dataset including multiple object blocks, where each storage memory is configured to store one or more of the object blocks of the dataset according to an erasure coding policy. The system includes one or more processors configured to implement the erasure coding policy by distributing the multiple object blocks of the dataset to the multiple storage memories according to distribution criteria of the erasure coding policy, and the distribution criteria include at least one status parameter associated with each storage memory. The multiple storage memories are geographically distributed at different locations from one another.

Abstract: A method for mapping LUNs (logical unit numbers) in storage memory, performed by a storage system, is provided. The method includes determining a set of LUNs in the storage memory and generating a mapping from a logical address space to all of the LUNs in the set, based on the determining, so that each logical address in the logical address space maps to one LUN in the set. The method includes accessing one or more of the LUNs in accordance with the mapping.

Abstract: Embodiments are directed to managing data in a file system that includes a plurality of storage nodes and a plurality of storage volumes in a cloud computing environment. Metrics associated with each storage volume may be monitored. In response to the metrics exceeding a threshold value, performing further actions, including: determining storage volumes that are unhealthy based on the metrics that exceed the threshold value; updating metadata associated with the storage volumes to indicate that the storage volumes are unhealthy; decoupling the unhealthy storage volumes from storage nodes coupled to the unhealthy storage volumes; determining replacement storage volumes based on the metadata associated with the unhealthy storage volumes; updating other metadata associated with the replacement storage volumes to indicate that the replacement storage volumes are healthy storage volumes; and coupling the healthy storage volumes with the storage nodes that were coupled to the unhealthy storage volumes.

Abstract: Techniques involve determining the number of disks in a Redundant Array of Independent Disks (RAID) storage system, and the storage system comprises multiple types of mixed disks. The techniques further involve determining a target number of RAID sets to be allocated in the storage system according to the number of disks and a predetermined threshold, and then allocating the multiple types of disks to the RAID sets according to the target number and types of disks. Such techniques propose a way to allocate mixed disks to the corresponding RAID sets. When the RAID set grouping is performed to mixed disks of the storage system, the same type of disks are allocated in the same RAID set as much as possible, thereby improving the performance of the storage system.

Abstract: A semiconductor storage device includes a first memory die. The first memory die includes a first memory plane including a plurality of first memory blocks, a second memory plane including a plurality of second memory blocks, a first sequencer, and a second sequencer. The first sequencer is configured to start a first write sequence with respect to one of the first memory blocks in response to a first command set designating the one of the first memory blocks if no write sequence is being performed by the first sequencer. The second sequencer is configured to start a second write sequence with respect to one of the second memory blocks in response to a second command set designating the one of the second memory blocks if the first sequencer is performing the first write sequence and no write sequence is being performed by the second sequencer.

Abstract: Methods and systems are provided for assigning nodes to execute functions in a serverless computing environment. In one embodiment, a method is provided that includes receiving a function for execution in a serverless computing environment and identifying a storage pool needed during execution of the function. The serverless computing environment may include nodes for executing functions and a first set of nodes may be identified that implement the storage pool. Colocation measures may be determined between the first set of nodes and a second set of nodes. Available computing resources may be determined for the second set of nodes, such as available processing cores and available memory. The second set of nodes may be ranked according to the colocation measures and the available computing resources and a first node may be selected based on the ranking. The first node may be assigned to execute the function.

Abstract: A USB-based cloud disk according to an embodiment is connected with a computer, and, when a write command on a sector is received from the computer, the USB-based cloud disk transmits data regarding the sector and a data path regarding the sector data to a remote repository.

Abstract: A method, a device, and a computer program product for creating a stripe in a storage system. In the method, a balance index of a storage device in multiple storage devices in the storage system is determined. Here, the balance index indicates a relationship between the state distribution of a set of stripes which have been allocated for use in the storage device and the state distribution of a set of stripes which have been allocated for use in the multiple storage devices. An influence factor for the balance index of the storage device in the multiple storage devices is determined according to attributes of the storage device in the multiple storage devices. A storage device for creating a stripe is selected from the multiple storage devices based on the determined balance index and the determined influence factor. One extent in the selected storage device is added to the stripe.

Abstract: A method for updating software of storage units of a set of storage units in a storage network. In an embodiment, each storage unit of the set of storage units determines a data slice storage status for data slices stored in the storage unit (e.g., by monitoring rebuilding messages relating to the data slices). A processing module of the storage network obtains the data slice storage status of the storage units of the set of storage units and determines whether to perform a software update to software of the storage units of the set of storage units. Determining whether to perform the software update includes determining, based on the data slice storage status of the storage units, whether a threshold number of storage units are associated with a favorable data slice storage status. In response to determining that a threshold number of storage units are associated with a favorable data slice storage status, the processing module indicates to perform the software update.

Abstract: A method includes acquiring, by a managing unit of a dispersed storage network (DSN), storage unit status information and data object storage status information from a plurality of storage units of DSN memory of the DSN. The method further includes determining, by the managing unit, DSN status information of the DSN memory based on the storage unit status information and the data object storage status information. The method further includes identifying, by the managing unit, DSN memory issues within the DSN memory. The method further includes prioritizing, by the managing unit, corrective remedies for the DSN memory issues based on the status information of the DSN memory. The method further includes facilitating, by the managing unit, the execution of the prioritized corrective remedies to correct the DSN memory issues.

Abstract: A storage device includes; an interface receiving data and a corresponding LBA from a host, wherein the data includes at least one of first data having a stream ID and second data lacking a stream ID, a nonvolatile memory (NVM) device including at least one nonvolatile memory configured to store the data, and a LBA predictor configured to provide a predicted stream ID for the second data using a neural network model operating in response to at least one feature associated with LBA values received by the storage device from the host, wherein the first data is stored in the NVM device using the stream ID, and the data is stored in the NVM device using the predicted stream ID.

Abstract: Improved management of user based input to a converged portable communication device is provided. A primary processor is configured to detect a user input feature request in response to a user interface control being activated. The primary processor determines whether the user input feature request is one of: a primary processor-centric request or a secondary processor-centric request. The primary processor retains primary requests and routes secondary requests to a secondary processor. If the secondary processor is unable to perform the requested feature, a check is made whether the primary processor is available and can fulfill the request as a secondary request. Positive user feedback is generated in response to determine that requests can be handled, and negative user feedback is generated when a requested feature cannot be handled.

Abstract: A copy-free transition tool converts storage objects from a source format associated with a source storage system to a destination format associated with a destination storage system. The transition tool exports configuration information associated with the source storage system to the destination storage system and brings the storage objects offline. Once the transition tool determines that the storage devices containing the storage objects are physically connected to the destination storage system, the tool can convert file systems from the source format to the destination format while leaving data and file layout unchanged. The tool can also modify metadata associated with each of the storage objects to conform to the destination format and store the modified metadata with the destination storage system.

Abstract: A method for optimizing memory usage in a device having a universal controlling application includes receiving into the device data for use in configuring the universal controlling application wherein the data is used to identify from within a library of command code sets stored in a memory of the device a command code set that is appropriate for use in commanding functional operations of the appliance and causing a non-identified one or more of the command code sets of the library of command code sets stored in the memory of the device to be discarded to thereby create freed space in the memory of the device.

Abstract: A dispersed storage (DS) unit for use within a dispersed storage network is capable of self-configuring using registry information provided to the DS unit. The registry information includes a slice name assignment indicating a range of slice names corresponding to a plurality of potential data slices of potential data objects to be stored in the DS unit. Based on the registry information, the DS unit allocates a portion of physical memory to store the potential data slices.

Abstract: Dynamically creating a communication path between first and second storage devices, includes creating a connection to a source volume on the first storage device and indicating that the source volume is not ready to transmit data on the communication path, after successfully creating the connection to the source volume, creating a connection to a destination volume on the second storage device and initially indicating that portions of one of: the destination volume and the source volume do not contain valid copies of data, where the destination volume accepts data from the source volume, and after successfully creating the connections to the source and destination volumes, indicating that the source volume is ready to transmit data on the communication path. Dynamically creating a communication path between first and second storage devices, may also include creating at least one of: the source volume and the destination volume.

Abstract: Replicated data storage units are autonomously identified and assembled into generationally related data storage volumes. A data storage manager, implementing a re-signaturing process executed at defined intervals or manually initiated on a server or client system connected to the storage area network, scans the collection of visible data storage units to identify those related as a data storage volume. Each replicated data storage unit includes metadata that embeds an identification of the replicated data storage unit and volume accessible to the data storage manager. To assemble a set of replicated data storage units into a generational volume, the data storage unit metadata is rewritten to establish a unique data storage volume identity including information to associate the data storage volume in a lineage with the source data storage volume.

Abstract: An electronic apparatus includes a memory control part that carries out allocation and deallocation of a memory area in a memory space; a memory reorganization part that carries out a reorganization process of moving the memory area allocated by the memory control part and creating a contiguous free space in the memory space; and a reorganization control part that causes the reorganization part to carry out the reorganization process in a case where a first predetermined condition is met, and does not cause the reorganization part to carry out the reorganization process in a case where a second predetermined condition different from the first predetermined condition is met.

Abstract: Described are techniques for enforcing an allocation policy. Information is received that describes one or more storage groups. Each of the storage groups includes one or more thin devices. Each of the thin devices includes a plurality of chunks of storage allocated on one or more of a plurality of storage tiers. For each of the one or more storage groups, a plurality of counters is determined indicating amounts of storage currently allocated from the plurality of storage tiers for use by the storage group. Using the plurality of counters, it is determined whether each of the one or more storage groups violates thresholds included in an allocation policy associated with each storage group. Each of the thresholds specifies a maximum amount of storage of one of the plurality of storage tiers that can be used by each storage group.

Abstract: The present invention is provided to make effective use of a storage area, and to enhance user usability. A management apparatus determines a reallocation destination of each logical storage area on the basis of an access load on each logical storage area by a host computer and an allocation status of each logical storage area in a storage-destination storage tier. A monitoring mode selection part for selecting any one of multiple monitoring modes selects a prescribed monitoring mode from the multiple monitoring modes on the basis of allocation time information related to a time at which each logical storage area is allocated to an allocation-destination storage tier.

Abstract: A storage device includes: a temporary buffer for sequentially storing data configuring a file requested to be written for every reception from outside; a data writing means for immediately separating the data in the temporary buffer into mutually corresponding data portion and marker portion classified by preset criteria and storing into a data storing means in an associated state, and deleting from the temporary buffer; an unseparated data writing means for storing the data that cannot be separated into the data portion and the marker portion among the data in the temporary buffer, into an unseparated data storing means; and a re-separation processing means for separating the data in the unseparated data storing means into the data portion and the marker portion by preset criteria and storing into the data storing means with the data portion and the marker portion associated, and deleting from the unseparated data storing means.

Abstract: Embodiments of the invention relate to optimizing a file system for different types of applications in a compute cluster using dynamic block size granularity. An exemplary embodiment includes reserving a predetermined number of storage allocation regions for each node in a cluster, wherein each storage allocation region comprises a set of contiguous data blocks on a single storage disk of locally attached storage; using a contiguous set of data blocks on a single storage disk of locally attached storage as a file system's block allocation granularity for striping data to be stored in the file system for a compute operation in the cluster; and using a single data block of a shared storage subsystem as the file system's block allocation granularity for striping data to be stored in the file system for a data access operation in the cluster.

Abstract: The present disclosure relates to the drift management for a memory device. In at least one embodiment, the memory device of the present disclosure may include a phase change memory and switch (hereinafter “PCMS”) memory cell and a memory controller that is capable of implementing drift management to control drift. Other embodiments are described and claimed.

Abstract: A method, system and computer-usable medium are disclosed for reordering User Data Segment (UDS) lists to reduce seek times when accessing data stored on tape media. A host application sends a list of UDSs to a target tape drive and requests the tape drive to reorder the list to provide better performance. An ordered list of target User data Segments to retrieve from a target tape media is received. Information related to the location of each UDS on the target media is processed to determine its corresponding physical position on the tape media. The resulting physical positions are then processed to generate a reordered UDS list, where the order of the User Data Segments is reordered according to their physical location on the target tape media. The reordered list of User Data Segments is then used to perform seek, reposition and read operations to read User Data Segments from the tape media.

Abstract: According to various embodiments, systems and methods are provided that relate to shared access to Storage Area Networks (SAN) devices. In one embodiment, a Storage Area Network (SAN) host is provided, comprising: a server component; a first host bus adapter configured to be connected to a SAN client over a first SAN; a second host bus adapter configured to be connected to a SAN storage device over a second SAN; and wherein the server component is configured to manage a data block on the SAN storage device, receive a storage operation request from the SAN client through the first host bus adapter, and in response to the storage operation request, perform a storage operation on the data block, the storage operation being performed over the second SAN through the second host bus adapter.

Abstract: Methods and structure are disclosed for normalizing storage performance across a plurality of logical volumes. One embodiment is a storage controller. The storage controller is adapted to couple with a plurality of host systems and a storage device. The storage controller is adapted to receive one or more requests to create logical volumes for the plurality of hose systems, and adapted to identify a plurality of performance zones for storage areas of the storage device. The performance zones exhibit different performance criteria for one or more of: reading data from the storage device and writing data to the storage device. The storage controller is further adapted to allocate storage from each of the plurality of performance zones for each of the plurality of logical volumes such that the performance criteria for accessing the storage device is distributed substantially uniformly across the plurality of logical volumes.

Abstract: A hybrid computing environment in which the host computer allocates, in the shadow memory area of the host computer, a memory region for a packet to be written to the shared memory of an accelerator; writes packet data to the accelerator's shared memory in a memory region corresponding to the allocated memory region; inserts, in a next available element of the accelerator's descriptor array, a descriptor identifying the written packet data; increments the copy of the head pointer of the accelerator's descriptor array maintained on the host computer; and updates a copy of the head pointer of the accelerator's descriptor array maintained on the accelerator with the incremented copy.

Abstract: A storage system is configured to manage a pool to which multiple virtual volumes (VVOLs) are associated, assign a real area (RA) from any tier in an available tier pattern associated with a write-destination VVOL to a write-destination virtual area (VA), and carry out a reassignment process for migrating data inside the RA to an RA of a different tier, based on an access status of the RA. A management system is configured to assume a specified tier has been removed from the available tier pattern of a target VVOL, predict performance of all VVOLs associated with the pool to which the target VVOL is associated, determine whether there is a VVOL for which predicted performance is lower than a required performance, and when such a VVOL does not exist, instruct the storage system to remove the specified tier from the available tier pattern of the target VVOL.

Abstract: A method and system for self-sizing dynamic cache for virtualized environments is disclosed. The preferred embodiment self sizes unequal portions of the total amount of cache and allocates to a plurality of active virtualized machines (VM) according to VM requirements and administrative standards. As a new VM may emerge and request an amount of cache, the cache controller reclaims currently used cache from the active VM and reallocates the unequal portions of cache required by each VM. To ensure cache availability, a quick reclamation amount of cache is immediately available to each new VM as it makes the request begins operation. After reallocation, the newly created VM may rely on a guaranteed minimum quota of cache to ensure performance.

Abstract: Systems and computer program products are provided for optimizing selection of files for deletion from one or more data storage devices to free up a predetermined amount of space in the one or more data storage devices. A method includes analyzing an effective space occupied by each file of a plurality of files in the one or more data storage devices, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for deletion, based on the identified one or more data blocks, and deleting the one or more candidate files for deletion from the one or more data storage devices.

Abstract: In accordance with the present disclosure, a system and method for performing a system memory save in tiered or cached storage during transition to a decreased power state is disclosed. As disclosed herein, the system incorporating aspects of the present invention may include a flash or other nonvolatile memory such as a solid-state drive, volatile memory, and at least one alternate storage media. Upon transition to a decreased power state, at least some of the data in the solid-state drive, for example, may be transferred to the at least one alternate storage media. After the SSD data is transferred, data stored in volatile system memory, such as a system context, may be transferred to the SSD memory. With the system context saved in SSD memory, power to the volatile system memory may be turned off.

Abstract: Systems and computer program products are provided for optimizing selection of files for eviction from a first storage pool to free up a predetermined amount of space in the first storage pool. A method includes analyzing an effective space occupied by each file of a plurality of files in the first storage pool, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for eviction, based on the identified one or more data blocks, and evicting the one or more candidate files for eviction from the first storage pool to a second storage pool.

Abstract: An approach to efficient space reclamation in multi-layered thinly provisioned systems. A parent storage volume is thinly provisioned, and uses one or more child storage volumes that are also thinly provisioned for storage. A reclamation command sent to the device providing the parent thinly provisioned storage volume identifies that data has been released, and that the physical storage storing that data can be placed in a free pool and used to satisfy future write requests in the parent storage volume. An identify module identifies which child storage volumes supporting the parent storage volume are thinly provisioned. The data is released at the level of the parent storage volume, and the reclamation command is sent to the child storage volumes supporting the parent storage volume and that are themselves thinly provisioned. The storage is thus released by all affected thinly provisioned storage volumes, and not just the parent storage volume that received the reclamation command.

Abstract: A storage system stores data in at least one partition of a physical storage media in accordance with file system information specifying a plurality of logical blocks having logical block addresses within the partition. The logical blocks include excess logical blocks that are not mapped to space in the physical storage media by the mapping employed by the storage system. Unusable block data marks those excess logical blocks as unusable. This makes it easy to adjust the data storage capacity of the storage system by changing the mapping to map more or less logical block addresses to space in the physical storage media and thereby destroy or create excess logical blocks, and by changing the unusable block data to correspondingly change the excess logical blocks marked as unusable.

Abstract: In one embodiment, the present invention includes a memory management unit (MMU) having entries to store virtual address to physical address translations, where each entry includes a location indicator to indicate whether a memory location for the corresponding entry is present in a local or remote memory. In this way, a common virtual memory space can be shared between the two memories, which may be separated by one or more non-coherent links. Other embodiments are described and claimed.

Abstract: Methods, systems, and computer program products are provided for optimizing selection of files for deletion from one or more data storage devices to free up a predetermined amount of space in the one or more data storage devices. A method includes analyzing an effective space occupied by each file of a plurality of files in the one or more data storage devices, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for deletion, based on the identified one or more data blocks, and deleting the one or more candidate files for deletion from the one or more data storage devices.

Abstract: A device requiring address allocation, a device system, and an address allocation method. A control device in the device system transmits currently allocated address information and a contention start signal to each device requiring address allocation in the device system through a bus, and the devices requiring address allocation with address allocation flag information being that no address information is allocated output an address contention signal. When outputting the address contention signal, each device requiring address allocation determines whether the currently allocated address information is available according to whether the other devices requiring address allocation with address allocation flag information being that no address information is allocated already output address contention signals.