Abstract: In an upper storage device, a BEPK and an MP are provided, each of a plurality of lower storage devices has a plurality of stripes configuring a plurality of stripe rows, each of the plurality of stripe rows is a row of two or more stripes which the plurality of lower storage devices have, respectively, when each of the plurality of stripe rows stores a plurality of data elements and a redundant code and a predetermined allowable number of lower storage devices fail, the data elements in the stripes can be restored and the MP controls a processing speed in restoration processing, on the basis of restoration priorities for the data elements or the redundant code of failed stripes in the failed lower storage devices.

Abstract: A storage system monitors the first access frequency of occurrence which is the access frequency of occurrence from a host device during a first period, and the second access frequency of occurrence which is the access frequency of occurrence from a host device during a second period shorter than the first period. Along with performing data relocation among the tiers (levels) in the first period cycle based on the first access frequency of occurrence, the storage system performs a decision whether or not to perform a second relocation based on the first access frequency of occurrence and the second access frequency of occurrence, synchronously with access from a host device. Here the threshold value utilized in a decision on whether or not to perform the first relocation is different from the threshold value utilized in a decision on whether or not to perform the second relocation.

Abstract: While an extra storage resource required for an operation of IaaS/PaaS is reduced, an SLA on storage performance is maintained even upon a failure. In a storage system including a plurality of storage nodes for providing storage regions for storing data of a computer on which an application is executed, a normal mode to be set in a normal state and an emergency mode in which a predetermined function is suppressed compared with the normal mode are prepared as a process mode for a request for input and output of data. In the storage system, in response to the occurrence of a failure in a first storage node, the process mode is switched to the emergency mode for a second storage node in which the failure does not occur.

Abstract: A storage system according to one aspect of the present invention includes a plurality of storage devices using flash memory as a storage medium. The flash memory used for the storage device may include flash memory configured to operate each cell as a cell capable of storing n-bit information or a cell capable of storing m-bit information (where n<m). The storage system may periodically acquire a number of remaining erasures from the storage device and predict the lifetime of the storage device by using the acquired number of remaining erasures and the storage device operation time. If the predicted lifetime is less than a predetermined value (service life) a predetermined number of cells may be changed to cells capable of storing n-bit information.

Abstract: This storage system is designed to: divide data into a plurality of chunk data (pieces of data) in a deduplication process; select one or more chunk data from among the plurality of chunk data in accordance with a sampling period which indicates that, on average, one chunk data be selected from among each N chunk data; and calculate a fingerprint, such as a hash value, for each of one or more characteristic chunk data, which are the selected one or more chunk data, and determine whether data including the one or more characteristic chunk data is a duplication. The storage system changes the sampling period on the basis of the results of past deduplication processes.

Abstract: To more effectively eliminate a resource imbalance among storage apparatuses, and shorten the time required for elimination in a computer system including a plurality of storage apparatuses and a computer. In a computer system including a plurality of storage apparatuses that provide a volume to a computer and a storage management device that manages the plurality of storage apparatuses, in a case where there is an instruction to create a new volume, the storage management device compares a distribution of feature amounts of all volumes provided by each storage apparatus and a distribution of feature amounts of all volumes in a case of providing a newly created volume in each storage apparatus, and instructs a storage apparatus having a largest difference in the distributions of the feature amounts to create a volume.

Abstract: An upper system of an NVM device transmits, to the NVM device, a write command that designates a logical address, the write command being associated with an expiration date corresponding to a data expiration date correlated with write target data. The NVM device correlates an expiration date correlated with the write command with a logical address specified from the write command. The NVM device writes pieces of data of which the remaining time which is the time to an expiration date belongs to the same remaining time range to the same physical storage area among the plurality of physical storage areas. The NVM device erases data from a physical storage area when the expiration dates of all pieces of data in the physical storage area have expired.

Abstract: The management computer has a memory which stores management information and management programs, and a CPU which refers to the management information and executes the management programs; the management information includes storage management information for allowing determination as to whether the plurality of storage resources can be paired in a redundant configuration, and couplable configuration management information for determining whether the plurality of storage resources and the plurality of server resources can be connected to each other; and when the CPU deploys a virtual machine, the CPU first determines, by reference to the storage management information, storage resources to be paired in a redundant configuration, then selects, by reference to the couplable configuration management information, server resources each of which can be connected to a respective one of the storage resources that are to be paired in a redundant configuration, and pairs the selected server resources in the redundant c

Abstract: A configuration aimed at reducing loads on storage apparatuses at a restoration site is provided in an environment where there are differences in the performance and capacity of the storage apparatuses between a primary site and the restoration site. Second volumes which form a remote copy with first volumes provided to a host at a primary site are located in a storage apparatus at the restoration site, which can satisfy the performance requirement upon failure of the first volumes, on the basis of performance information and available capacity information. A volume group is configured for each of the second volumes located at one storage apparatus at the restoration site and the first volumes; and an extended volume group including a plurality of second volumes, in which data is replicated and recorded in a write order to write the data to the first volumes, and their first volumes is set.

Abstract: The performance of a computer system which distributes and stores user data and a redundant code is improved. Each computer generates group information indicating positions of a user data region and a redundant code region in each of a plurality of computers; when a write request for write data is received, each computer writes the write data to a local storage device, selects a transmission destination computer on the basis of the group information, and transmits transmission data to the transmission destination computer; when a plurality of pieces of transmission data are respectively received, each computer generates a redundant code by using the plurality of pieces of transmission data on the basis of the group information, and writes the redundant code to the local storage device; and when configurations of the plurality of computers are changed, each computer changes the group information on the basis of the changed configurations.

Abstract: A computer system includes a plurality of computer nodes communicating with each other via a network. Each of the plurality of computer nodes includes a local storage and at least one virtual machine. Each of the plurality of computer nodes transfers write data for the local storage to at least one different computer node for redundancy. A computer included in the computer system is configured to: obtain information indicating a write load amount of a first virtual machine; obtain information indicating remaining writable space of a local storage of a destination computer node among the plurality of computer nodes; and determine whether or not the first virtual machine should be transferred to the destination computer node, based on the write load amount of the first virtual machine and the remaining writable space of the destination computer node.

Abstract: A storage system according to one aspect of the present invention includes a plurality of storage devices using flash memory as a storage medium. The flash memory used for the storage device may include flash memory configured to operate each cell as a cell capable of storing n-bit information or a cell capable of storing m-bit information (where n<m). The storage system may periodically acquire a number of remaining erasures from the storage device and predict the lifetime of the storage device by using the acquired number of remaining erasures and the storage device operation time. If the predicted lifetime is less than a predetermined value (service life) a predetermined number of cells may be changed to cells capable of storing n-bit information.

Abstract: The performance of a computer system which distributes and stores user data and a redundant code is improved. Each computer generates group information indicating positions of a user data region and a redundant code region in each of a plurality of computers; when a write request for write data is received, each computer writes the write data to a local storage device, selects a transmission destination computer on the basis of the group information, and transmits transmission data to the transmission destination computer; when a plurality of pieces of transmission data are respectively received, each computer generates a redundant code by using the plurality of pieces of transmission data on the basis of the group information, and writes the redundant code to the local storage device; and when configurations of the plurality of computers are changed, each computer changes the group information on the basis of the changed configurations.

Abstract: A computer system includes a plurality of computer nodes communicating with each other via a network. Each of the plurality of computer nodes includes a local storage and at least one virtual machine. Each of the plurality of computer nodes transfers write data for the local storage to at least one different computer node for redundancy. A computer included in the computer system is configured to: obtain information indicating a write load amount of a first virtual machine; obtain information indicating remaining writable space of a local storage of a destination computer node among the plurality of computer nodes; and determine whether or not the first virtual machine should be transferred to the destination computer node, based on the write load amount of the first virtual machine and the remaining writable space of the destination computer node.

Abstract: A storage system monitors the first access frequency of occurrence which is the access frequency of occurrence from a host device during a first period, and the second access frequency of occurrence which is the access frequency of occurrence from a host device during a second period shorter than the first period. Along with performing data relocation among the tiers (levels) in the first period cycle based on the first access frequency of occurrence, the storage system performs a decision whether or not to perform a second relocation based on the first access frequency of occurrence and the second access frequency of occurrence, synchronously with access from a host device. Here the threshold value utilized in a decision on whether or not to perform the first relocation is different from the threshold value utilized in a decision on whether or not to perform the second relocation.

Abstract: This storage system is designed to: divide data into a plurality of chunk data (pieces of data) in a deduplication process; select one or more chunk data from among the plurality of chunk data in accordance with a sampling period which indicates that, on average, one chunk data be selected from among each N chunk data; and calculate a fingerprint, such as a hash value, for each of one or more characteristic chunk data, which are the selected one or more chunk data, and determine whether data including the one or more characteristic chunk data is a duplication. The storage system changes the sampling period on the basis of the results of past deduplication processes.

Abstract: A configuration aimed at reducing loads on storage apparatuses at a restoration site is provided in an environment where there are differences in the performance and capacity of the storage apparatuses between a primary site and the restoration site. Second volumes which form a remote copy with first volumes provided to a host at a primary site are located in a storage apparatus at the restoration site, which can satisfy the performance requirement upon failure of the first volumes, on the basis of performance information and available capacity information. A volume group is configured for each of the second volumes located at one storage apparatus at the restoration site and the first volumes; and an extended volume group including a plurality of second volumes, in which data is replicated and recorded in a write order to write the data to the first volumes, and their first volumes is set.

Abstract: The management computer has a memory which stores management information and management programs, and a CPU which refers to the management information and executes the management programs; the management information includes storage management information for allowing determination as to whether the plurality of storage resources can be paired in a redundant configuration, and couplable configuration management information for determining whether the plurality of storage resources and the plurality of server resources can be connected to each other; and when the CPU deploys a virtual machine, the CPU first determines, by reference to the storage management information, storage resources to be paired in a redundant configuration, then selects, by reference to the couplable configuration management information, server resources each of which can be connected to a respective one of the storage resources that are to be paired in a redundant configuration, and pairs the selected server resources in the redundant c

Abstract: A storage system monitors the first access frequency of occurrence which is the access frequency of occurrence from a host device during a first period, and the second access frequency of occurrence which is the access frequency of occurrence from a host device during a second period shorter than the first period. Along with performing data relocation among the tiers (levels) in the first period cycle based on the first access frequency of occurrence, the storage system performs a decision whether or not to perform a second relocation based on the first access frequency of occurrence and the second access frequency of occurrence, synchronously with access from a host device. Here the threshold value utilized in a decision on whether or not to perform the first relocation is different from the threshold value utilized in a decision on whether or not to perform the second relocation.

Abstract: A computer system that is composed of a host computer, a storage device and a management computer. The storage device comprises a port for connecting with the host computer, a cache memory, a processor, and a plurality of logic volumes which are logical memory regions. For each logic volume, the port, the cache memory and the processor are divided into logic partitions, as resources that are used for reading and writing in the logic volume. The host computer reads and writes with respect to the logic volumes. If a failure occurs in the storage device, the management computer issues a command to the storage device to allocate the resources of a logic partition for which reading/writing performance is not ensured to a logic partition for which reading/writing performance is ensured.