Abstract: Some embodiments of the present invention relate to a method and a circuit for managing the prefetching of data into a cache. According to some embodiments of the present invention a prefects controller may be adapted to trigger a prefetch operation for prefetching one or more data segments into the cache together with at least one segment to be fetched, and may be further adapted to establish a number of data segments to be prefetched together with the at least one segment to be fetched. According to some embodiments of the present invention, the prefetch controller may be adapted to establish what number of segments are to be prefetched at least in accordance with the number of successive segments, including one, already in the cache, which are spaced apart by no more than a predetermined number of segments relative to the at least one segment to be fetched.

Abstract: A method for managing multiple logical volumes in a data storage system, including providing physical storage of a given capacity within the data storage system, and adding a logical volume of a given size within the data storage system so as to cause a total amount of logical storage of the logical volumes in the data storage system to be greater than the given capacity of the physical storage. The method includes verifying, in response to a write command to store data in the logical volume, that a physical storage location is available in the physical storage and, if the physical storage location is available, then storing the data at the physical storage location.

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: 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: 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: 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: A method for reading data from a data storage system, consisting of storing a plurality of copies of the data at a respective plurality of data storage units and receiving at a data port an access request submitted by a host to receive the data. The method further includes transmitting from the port, in response to the access request, a plurality of delivery requests for the data to the respective plurality of data storage units, transmitting from the plurality of data storage units to the port respective responses to the delivery requests, the responses including the data, and accepting at the port an earliest-arriving response consisting of the response to the delivery requests arriving first at the port. The data in the earliest-arriving response is forwarded from the port to the host.