2418 results about "Disk array" patented technology

The present invention is a method for integrating a file system with a RAID array that exports precise information about the arrangement of data blocks in the RAID subsystem. The file system examines this information and uses it to optimize the location of blocks as they are written to the RAID system. Thus, the system uses explicit knowledge of the underlying RAID disk layout to schedule disk allocation. The present invention uses separate current-write location (CWL) pointers for each disk in the disk array where the pointers simply advance through the disks as writes occur. The algorithm used has two primary goals. The first goal is to keep the CWL pointers as close together as possible, thereby improving RAID efficiency by writing to multiple blocks in the stripe simultaneously. The second goal is to allocate adjacent blocks in a file on the same disk, thereby improving read back performance. The present invention satisfies the first goal by always writing on the disk with the lowest CWL pointer. For the second goal, a new disk is chosen only when the algorithm starts allocating space for a new file, or when it has allocated N blocks on the same disk for a single file. A sufficient number of blocks is defined as all the buffers in a chunk of N sequential buffers in a file. The result is that CWL pointers are never more than N blocks apart on different disks, and large files have N consecutive blocks on the same disk.

A method is disclosed for integrating a file system with a RAID array that exports precise information about the arrangement of data blocks in the RAID subsystem. The file system examines this information and uses it to optimize the location of blocks as they are written to the RAID system. Thus, the system uses explicit knowledge of the underlying RAID disk layout to schedule disk allocation. The method uses separate current-write location (CWL) pointers for each disk in the disk array where the pointers simply advance through the disks as writes occur. The algorithm used has two primary goals. The first goal is to keep the CWL pointers as close together as possible, thereby improving RAID efficiency by writing to multiple blocks in the stripe simultaneously. The second goal is to allocate adjacent blocks in a file on the same disk, thereby improving read back performance. The method satisfies the first goal by always writing on the disk with the lowest CWL pointer. For the second goal, a new disks chosen only when the algorithm starts allocating space for a new file, or when it has allocated N blocks on the same disk for a single file. A sufficient number of blocks is defined as all the buffers in a chunk of N sequential buffers in a file. The result is that CWL pointers are never more than N blocks apart on different disks, and large files have N consecutive blocks on the same disk.

An efficient method to apply an erasure encoding and decoding scheme across dispersed data stores that receive constant updates. A data store is a persistent memory for storing a data block. Such data stores include, without limitation, a group of disks, a group of disk arrays, or the like. An encoding process applies a sequencing method to assign a sequence number to each data and checksum block as they are modified and updated onto their data stores. The method preferably uses the sequence number to identify data set consistency. The sequencing method allows for self-healing of each individual data store, and it maintains data consistency and correctness within a data block and among a group of data blocks. The inventive technique can be applied on many forms of distributed persistent data stores to provide failure resiliency and to maintain data consistency and correctness.

A failure predicting unit predicts a failure in a hard disk device that forms a disk array. A data transferring unit transfers data from a failure-predicted hard disk device for which the failure is predicted by the failure predicting unit to a spare disk. A data deleting unit deletes the data from the failure-predicted hard disk device after the data transferring unit completes transferring the data.

If a disk fails, another disk is used to rebuild the data of the failed disk on a first spare disk. When finishing being rebuilt, the first spare disk is separated from the disk array apparatus. Data to be updated while the first spare disk separated is written in another disk and managed by a bit map. The first spare disk is connected to the disk array apparatus at the position of the failed disk, then only the updated data is rebuilt on the first spare disk using another disk.

A cached disk array includes a disk storage array, a global cache memory, disk directors coupling the cache memory to the disk storage array, and front-end directors for linking host computers to the cache memory. The front-end directors service storage access requests from the host computers, and the disk directors stage requested data from the disk storage array to the cache memory and write new data to the disk storage. At least one of the front-end directors or disk directors is programmed for block resolution of virtual logical units of the disk storage, and for obtaining, from a storage allocation server, space allocation and mapping information for pre-allocated blocks of the disk storage, and for returning to the storage allocation server requests to commit the pre-allocated blocks of storage once data is first written to the pre-allocated blocks of storage.

According to one embodiment, a disk array control device manages a plurality of drives as a single logical drive. The disk array control device includes a first register configured to store a to-he-accessed drive number which is designated by a host, and a control module. The control module is configured to receive a command from the host, determine whether the received command is a predetermined command which is used for maintenance of each of the drives, and execute, in a case where the received command is the predetermined command, a pass-through process of sending the received command to the drive which is designated by the to-be-accessed drive number in the first register.

A system and method for replacing file system processors, also known as hot swapping, is described. The system and method operate on a fault-tolerant network file system that includes a first file server that is operably connected to a network fabric and a second file server that is operably connected to the network fabric. The fault-tolerant network file system includes a first disk array that is operably coupled to the first file server and to the second file server and a second disk array that is operably coupled to the first file server and to the second file server. First file system information is loaded on the first file server. The first file system information includes a first intent log of proposed changes to first metadata. Second file system information is loaded on the second file server. The second file system information includes a second intent log of proposed changes to second metadata. The first file server has a copy of the second metadata, and the second file server maintains a copy of the first metadata, thereby allowing the first file server to access files on the second disk array in the event of a failure of the second file server.

A multimedia server system includes a disk array subsystem including a plurality of multimedia files, e.g., movies, a media file system manager for managing the storage of the plurality of multimedia files within the disk array subsystem, and a playlist which includes a list of titles of specific multimedia files to be played at designated times. The multimedia server system advantageously includes synchronization parameters associated with each of titles specified by the playlist. The synchronization parameters are programmed to specify the manner in which particular files should be truncated in order to compensate for admission delays. An admission delay synchronization unit receives the synchronization parameters and truncates the multimedia files as specified by the synchronization parameters. In one implementation, a first synchronization parameter is used to specify that the current file should be truncated at the time for the play of the next file. A second synchronization parameter specifies that up to a given amount of time should be sacrificed at the beginning of the next file to account for the admission delay of the current file. In this manner, the beginning of the next file is truncated. Still a third synchronization parameter is provided to specify an amount of time up to which the current file will be truncated at it's end to account for it's admission delay. As a result, the truncated file can be played in a shorter amount of time than the scheduled duration, and the "excess time" created is available to absorb any admission delay.

A system and method for linking external storage systems that includes creating a virtual volume mapping at one or more storage systems. Each virtual volume mapping at each storage system associating a virtual storage volume with a physical storage volume and / or one second virtual storage volume at one or more second storage systems. An access request is received at a first storage system specifying a virtual volume. It is determined on which storage system a physical storage volume associated with the specified virtual volume in the access request is located using the virtual volume mapping at the first storage system and / or the virtual volume mapping at one or more second storage systems. Access is provided to the physical storage volume based on which storage system the physical storage volume is located. Useful in Storage Area Networks and many configurations including 1 to 1, dual path, mirrored, and concatenated, etc.

An approach is provided for integrated content delivery. A request for content stored on a disk array of a router is received. In response to the request, one or more disks of the disk array are selected to retrieve the content, wherein the disk array is natively coupled to a switch fabric of the router. A path is determined through the switch fabric for transmission of the content.

A disk array apparatus including a rack-shaped basic frame, and a plurality of disk boxes that can be inserted into and pulled out of the basic frame depth-wise. Each disk box has: disk drive connectors for connecting a plurality of disk drives arranged in a matrix on a platter substrate, which is the bottom face of the disk box, roughly parallel to the depth direction of the basic frame; and a cooling module for cooling the disk drives. The disk box is a hermetically sealed structure.

The invention is intended to reduce disk access during data transfer from a disk in which occurrence of failure is anticipated to a spare disk as much as possible so that occurrence of double-failure is prevented in advance. When occurrence of failure in a disk which configures a RAID group, contents stored in the disk is copied to the spared disk. Simultaneously, another RAID group is paired with the above described RAID group and a secondary volume is provided therein. A write request is directed to the secondary volume. A differential bitmap controls a update data. Data which is not updated is read out from the primary volume, and data which is already updated is read from the secondary volume. When data transfer is completed, contents stored in the secondary volume are copied to the primary volume.

A disk array includes a drive management unit, which is a program for identifying types of disk devices and managing different disk devices separately, and a drive management table for storing information to be utilized by the drive management unit. The disk array further includes a program for managing accumulated time of disk devices. The program includes a drive lifetime setting portion for setting lifetimes of drives, a drive start / stop portion for intentionally starting / stopping ATA disk devices, and an operation time measurement portion for measuring accumulated operation time. Since it is necessary to be conscious of difference in reliability and performance among disk devices when forming a RAID, a drive type notification unit, which is a program for notifying of the type of a disk device when forming the RAID, is provided.

Load balancing of activities on physical disk storage devices is accomplished by monitoring reading and writing operations to blocks of contiguous storage locations on the physical disk storage devices. A list of exchangeable pairs of blocks is developed based on size and function. Statistics accumulated over an interval are then used to obtain access activity values for each block and each physical disk drive. A statistical analysis leads to a selection of one block pair. After testing to determine any adverse effect of making that change, the exchange is made to more evenly distribute the loading on individual physical disk storage devices.

A method for backing up the data of a disk array system having network file server and storage area network functions easily and rapidly without using a route for data to be not backed up. Upon receipt of a backup request, a network file server module copies files on the disk array system's regular volumes to a backup volume. The network file server module then requests a storage area network module to copy the files to an external storage device. Finally, the storage area network module copies the current contents of the backup volume to the external storage device. The network file server module can limit the data to be backed up, thereby reducing the backup time requirements. The load on a LAN does not increase because the storage area network module acquires the data to be backed up. The processing speed increases thanks to backup load distribution within the disk array system.

A disk array includes a system and method for cache management and conflict detection. Incoming host commands are processed by a storage controller, which identifies a set of at least one cache segment descriptor (CSD) associated with the requested address range. Command conflict detection can be quickly performed by examining the state information of each CSD associated with the command. The use of CSDs therefore permits the present invention to rapidly and efficiently perform read and write commands and detect conflicts.

A disk array control device which includes a plurality of channel interface (IF) units, a plurality of disk IF units, a cache memory unit, and a shared memory unit. The connection system between the plurality of channel IF units and plurality of disk IF units and the cache memory unit is different from the connection system between the plurality of channel IF units and plurality of disk IF units and the shared memory unit. In the invention the plurality of channel IF units and the plurality of disk IF units are connected via a selector to the cache memory unit, whereas the plurality of channel IF units and the plurality of disk IF units are directly connected to the shared memory unit with no selectors.

In a computer system with a disk array that has physical storage devices arranged as logical storage units and is capable of carrying out hardware storage operations on a per logical storage unit basis, a third party server is provided to offload storage operations from a file system to storage hardware. The third party server transfers configuration information associated with composite storage operations to the physical storage devices through an out-of-band path to enable composite storage operations to be executed without involving the file system.

The invention relates to the server switch method, wherein when the primary host fails, with the server negotiation, deciding whether the standby server takes over the service of the primary server, and switching the servers for primary-standby state. This invention can avoid using disc array, reduces switch cost, and improves system reliability.

A NAS (network attached storage) controller managing file system data is configured for use in a storage system having thin provisioning capability. Physical storage capacity is used efficiently by making it possible for the NAS controller to identify to a disk array system having thin provisioning capability which segments of a thin provisioned volume are no longer in use. File system blocks or block groups no longer in use by the NAS controller are identified by the NAS controller. The NAS controller sends a release request to the disk array system specifying thin provisioning segments that correspond to the identified FS blocks or block groups. The release request instructs the disk array system to release chunks of physical storage capacity assigned to the specified thin provisioning segments so that the physical storage capacity can be made available for reuse in the disk array storage system.

A controller retrieves effective logical addresses sequentially according to a copy of an address translation table at the time of the start of storage capacity expansion in the process of expanding the storage capacity of a disk array by adding a disk drive to the disk array. The controller stores the data in the logical address into a restructured write buffer each time an effective logical address is retrieved. The controller writes one stripe worth of data blocks including one stripe of logical blocks and a logical address tag block into an empty area different from the area in which the data to be updated has been stored in the data array each time one stripe worth of logical blocks of data is accumulated in the write buffer.

A disk array connected to a storage area network via a fiber channel has one or more ports each controlled by a processor. Even the disk array with one port and one processor executes online processing and backup processing at the same time while considering an online processing load. A port controller not only accepts a request from a host computer but issues a request to other storage controllers to allow online processing and backup processing to be executed at the same time. In addition, the disk array, if provided with a plurality of ports, selects ports or schedules processing depending upon the load to prevent backup processing from affecting online processing performance.

A method of writing image data files to frame storage means, implemented as an array of disks, on which image data is stored as contiguous clips of frames. A remote system transmits a plurality of data packets over a network in any order, the data packets constituting a plurality of image data files. A local system connected to the frame storage means receives the data packets from the remote system and stores them in a buffer so as to arrange the image data files in a display sequence order. The local system then writes the image data files to the frame storage means as a contiguous clip of frames.