Abstract: A method for operating a storage system, including storing data redundantly in the system and measuring respective queue lengths of input/output requests to operational elements of the system. The queue lengths are compared to an average queue length to determine respective performances of the operational elements of the storage system. In response to the average queue lengths and a permitted deviation from the average an under-performing operational element among the operational elements is identified. An indication of the under-performing operational element is provided to host interfaces in the storage system. One of the host interfaces receives requests for specified items of the data directed to the under-performing element, and in response to the indication, some of the requests are diverted from the under-performing operational element to one or more other operational elements of the storage system that are configured to provide the specified items of the data.

Abstract: A method for data storage, including configuring in a data storage system a volume storage pool as data storage resources available for allocation of volumes in the data storage system. The method also includes defining a threshold value for the volume storage pool. When the allocation of the volumes causes the threshold value to be crossed, the method includes performing an action for managing the volume storage pool.

Abstract: A method for interfacing with a storage system. The storage system has a plurality of elements having a visible relationship with each other, and the storage system is coupled to a system control unit including a display. The method includes: drawing an image of the elements on the display, the image showing the visible relationship, and modifying an appearance of one of the elements in the image to represent a property of the element. The method further includes, in response to a first input from a user of the storage system to the system control unit, drawing an enlarged image of the element and representing the property in the enlarged image. The method also includes, in response to a second input from a user of the storage system to the control unit with respect to the enlarged image, representing a further property of the element in the enlarged image.

Abstract: Disclosed is a system, method and circuit for mirroring data on a data server. According to some embodiments of the present invention, a primary mirroring module associated with a primary server may be adapted to establish data mirroring connections between the primary server and both a primary slave mirroring module functionally associated with a primary mirror server and with a secondary slave mirroring module functionally associated with a secondary mirror server. When sensing that a mirroring connection with the primary server has been terminated, the primary slave mirroring module may establish a mirroring connection with the second slave mirroring module and may reconcile data between the primary and secondary mirror servers.

Abstract: According to some embodiments of the present invention, a data storage system may include a plurality of controllers connected or otherwise associated with one or more mass data storage devices. One controller may signal to one or more other controllers an indication as for which data blocks it has received requests. A prefetch decision module on a controller may decide to prefetch some or all of the data blocks associated with a given logical data unit based on data block requests it has received and based on requests received by other controllers. A prefetch decision module on a first controller may signal one or more other controllers to prefetch one or more data blocks associated with a given logical unit and which reside on mass storage devices either connected or otherwise associated with each of the one or more controllers.

Abstract: Some embodiments of the invention relate to a method of managing a distributed compression system comprised of a plurality of compression modules.

Abstract: A method for data mirroring including receiving a sequence of transactions at a first storage node from a host indicating data to be stored by the node, storing the data therein, and delineating a first batch of the transactions. The node returns to the host an acknowledgment of having stored the data, delineates a second batch of the transactions received subsequent to the acknowledgment, and conveys the data to a second storage node. The first node also conveys to the second node a first record of the transactions in the first batch and a second record of the transactions in the second batch, and the data are stored in the second node responsively to the first and second records, so that all data indicated by the transactions in the first batch are stored by the second node prior to storing data indicated by the transactions in the second batch.

Abstract: A method for storing data blocks, including forming the data blocks into groups comprising N·M data blocks, where N and M are different positive integers. For every group, the N·M data blocks are assigned to correspond to elements of an array comprising N rows and M columns. A respective parity block is calculated for each of the N rows and M columns, to form (N+M) parity blocks. The resulting (N+M) parity blocks and N·M data blocks are stored in respective storage devices.

Abstract: A method for managing a storage system, including storing first and second sets of data on a storage device in the system. The method further includes assigning a first restore preference level to the first set and a second restore preference level to the second set, such that applying the first level and the second level respectively to the first and second sets rebuilds the first set before the second set irrespective of physical locations and logical addresses of the sets on the storage device. The method also includes receiving an indication of a failure in the storage device, generating a command to rebuild the first set as a first restored set and the second set as a second restored set, and in response to the command, rebuilding the first set of the data and the second set of the data according to the respective restore preference levels.

Abstract: Some embodiments of the invention relate to an apparatus and a method of managing a snapshot storage pool (SSP) associated with a storage unit of a distributed data storage system. According to some embodiments of the invention, the apparatus may include a logic module and a controller. The logic module may be adapted to provide a threshold corresponding to a ratio between a current amount of storage resources used for storing snapshots in the SSP and a total storage capacity defined for the SSP. The controller may be adapted to trigger an action which may be effective for managing the SSP in response to the amount of storage resources used for storing snapshots in the SSP crossing the threshold.

Abstract: As part of some embodiments of the present invention, there is provided a method, a circuit and a system for managing data in a cache memory of a mass data storage device and/or system. In accordance with some embodiments of the present invention, a data portion's priority in the cache may be altered. The priority of the data portion may be altered as a function of an access parameter associated with the data portion and a fetch parameter associated with the data portion.

Abstract: A method for storing data, consisting of distributing a first plurality of groups of logical addresses among one or more storage devices in a storage system, receiving a second plurality of data-sets containing the data to be stored, and assigning each data-set among the plurality of data-sets a random number chosen from a first plurality of different numbers. The method further consists of partitioning each data-set into multiple partitions, so that each partition among the multiple partitions receives a sequential partition number, assigning each partition within each data-set to be stored at a specific group of logical addresses in the storage system in accordance with the sequential partition number of the partition and the random number assigned to the data-set, and storing each partition in the storage system at the assigned specific group of logical addresses.

Abstract: Disclosed is a system, method and circuit for mirroring data on a data server. According to some embodiments of the present invention, a primary mirroring module associated with a primary server may be adapted to establish data mirroring connections between the primary server and one or more mirror sever systems. According to some embodiments of the present invention, the primary mirroring module includes an evaluator unit which generates a delta file to be transmitted to the one or more mirror server systems.

Abstract: A method for managing activity of a data storage system including a primary storage facility and a secondary storage facility. The method includes mirroring a first logical unit in the primary facility on a second logical unit in the secondary facility, and receiving a command to perform a data storage management activity on the first logical unit. The method further includes synchronizing the second logical unit with the first logical unit responsive to the command, and performing the command on the first logical unit and the second logical unit simultaneously following synchronization.

Abstract: A storage system, including: one or more mass storage devices, coupled to store data at respective first ranges of logical addresses (LAs), and one or more interfaces, which are adapted to receive input/output (IO) requests from host processors directed to specified LAs. The system also includes a plurality of caches coupled to the one or more interfaces so as to receive the IO requests therefrom, each cache being assigned a respective second range of the LAs and being coupled to the one or more mass storage devices, the respective first ranges of which overlap the respective second range, so as to receive data from and provide data to the one or more mass storage devices, and being coupled to accept the IO requests within the respective second range directed thereto.

Abstract: A system for transferring data to and from one or more slow-access-time-mass-storage nodes which store data at respective first ranges of logical block addresses (LBAs), including a plurality of interim-fast-access-time nodes which are configured to operate independently of one another. Each interim-fast-access-time node is assigned a respective second range of the LBAs and is coupled to receive data from and provide data to the one or more slow-access-time-mass-storage nodes within the respective second range. The system further includes one or more interface nodes, which are adapted to receive input/output (IO) requests from host processors directed to specified LBAs and to direct all the IO requests to the interim-fast-access-time node to which the specified LBAs are assigned.

Abstract: A method for interfacing with a storage system having a plurality of elements, the elements having a visible relationship with each other, and being coupled to a system control unit including a display. The method includes drawing an image of the elements on the display, the image having the visible relationship and modifying the image of one of the elements to represent a property of the element. The method further includes, in response to an input from a user of the storage system to the system control unit, making a change in the property of the element and representing the change in the image.

Abstract: A method for data mirroring including receiving a sequence of transactions at a first storage node from a host indicating data to be stored by the node, storing the data therein, and delineating a first batch of the transactions. The node returns to the host an acknowledgment of having stored the data, delineates a second batch of the transactions received subsequent to the acknowledgment, and conveys the data to a second storage node. The first node also conveys to the second node a first record of the transactions in the first batch and a second record of the transactions in the second batch, and the data are stored in the second node responsively to the first and second records, so that all data indicated by the transactions in the first batch are stored by the second node prior to storing data indicated by the transactions in the second batch.

Abstract: Disclosed is system and method for mirroring data from a primary data storage system on a mirroring data storage system. According to some embodiments to the present invention, prior to resynchronization of a data unit on the mirroring system with corresponding data on a primary unit, a consistent snap-shot of the data unit to be resynchronized is taken. According to some embodiments of the present invention, the snap-shop may be discarded upon completion of resynchronization.

Abstract: Disclosed is a data processing and/or storage system. The data processing and/or storage system may include at least two interfaces, wherein each of the at least two interfaces includes a non-dedicated communication port for communicating data to and form external data systems or clients based on a rule base.