Abstract: According to certain aspects, the presently disclosed subject matter includes a method, system and apparatus, for managing a plurality of disk drives in a storage system. The workload of at least one disk drive among the plurality of disk drives is monitored, wherein the monitoring comprises receiving data indicative of a temperature of the at least one disk drive. In case the measured temperature matches a predefined criterion, the modification of workload distribution across the plurality of disk drives is enabled, in order to reduce workload of the at least one disk drive.

Abstract: A method and system are disclosed for storage optimization. Data parts and metadata within a source data unit are identified and the data parts are compared with data which is already stored in the physical storage space. In case identical data parts are found within the physical storage, the data parts from the source data unit are linked to the identified data, while the data parts can be discarded, thereby reducing the required storage capacity. The metadata parts can be separately stored in a designated storage area.

Abstract: A method for hot backward compatible upgrade of a storage system includes: a) configuring each virtual partition (VP) to be controlled by a primary data server and a secondary data server b) configuring each data server to have primary responsibility over all logical block addresses (LBAs) corresponding to at least two virtual partitions and to have secondary responsibility over all LBAs corresponding to at least two other virtual partitions; c) responsive to a shut-down of a data server, i) re-configuring primary responsibility over each VP previously primary controlled by the shut-down server such that it becomes primary controlled by a server previously configured as a secondary server with respect to this VP; ii) re-allocating secondary responsibility over each VP previously secondary controlled by the shut-down server in a manner that each such VP becomes secondary controlled by a server other than the newly assigned server with primary responsibility.

Abstract: The is provided a storage system comprising a plurality of disk units adapted to store data at respective ranges of logical block addresses (LBAs), said addresses constituting an entire address space, and a storage control grid operatively connected to the plurality of disk units and comprising a plurality of data servers.

Abstract: According to the presently disclosed subject matter there is provided, inter alia, a system and method which enable to identify, in a storage-system, malfunctioning disks, and in response, to activate a power-cycle process only for the specific failing disks, in order to bring these disks into proper operational mode. During the power-cycle process of a failing disk, other disks, which are not failing, remain operative and available.

Abstract: According to the presently disclosed subject matter there is provided inter alia, a method and system which enable to uncover errors which are correctable by a data integrity mechanism in a computer system. The same data is read with the help of two different types of read commands. The first command is a read command which does not implement an inherent ECC and therefore does not correct corrupted data. The second command is a read command which includes an ECC and is adapted to correct errors which are detected in the data which is being read. The data obtained by each of the two read commands is compared, and in cases where a difference is identified between the two data, it is determined that an error has been detected and corrected by the ECC.

Abstract: There is provided a method of operating a multipath storage system, the method comprises: identifying a primary storage control port configured to be responsible for a given LBA range and a secondary storage control port configured to have secondary responsibility for the given LBA range; reducing, in a manner unaffecting respective inbound I/O operation, outbound I/O operation related to the given LBA range and occurring at the primary storage control port, thereby causing a situation requiring switching all respective I/O requests to an alternating path; analyzing responsive changes in outbound I/O operation related to the given LBA range and occurring at the secondary storage control port, and verifying operability of switching to the alternating path in accordance with the obtained results.

Abstract: SAS technology does not offer an explicit solution to the identification of the physical location of an end device. Accordingly, there is provided a method and system for enabling to identify the physical location of a disk in a storage system configured with SAS technology. According to the presently disclosed subject matter a control device in a storage system is operable to determine the physical location of the disks within each enclosure. The control device can be made operable also to determine the location of the enclosures within the rack and thereby obtain the full mapping of the disks within the storage system. This mapping enables, inter alia, to associate between a SCSI target number of a disk and its physical location within the storage system.

Abstract: A method of migrating data from a source storage resource to a destination storage resource involves selecting a source volume in the source storage resource; configuring in the destination storage resource a destination volume corresponding to the source volume and having the same properties; and redirecting I/O requests from an application running on a host to the destination volume instead of the source volume, whilst migrating data stored in the source volume to the destination volume. A storage system is operable as a destination storage system for migrating data from a source storage system, including means for configuring a destination volume corresponding to a source volume in the source storage system and a migration module having a non-transitory computer useable medium and operable to initiate read requests addressed to the source volume thereby enabling a background process of migrating data stored in the source volume to the destination volume.

Abstract: A method and system are disclosed for storage optimization. Data parts and metadata within a source data unit are identified and the data parts are compared with data which is already stored in the physical storage space. In case identical data parts are found within the physical storage, the data parts from the source data unit are linked to the identified data, while the data parts can be discarded, thereby reducing the required storage capacity. The metadata parts can be separately stored in a designated storage area.

Abstract: A storage system and method is provided including physical storage devices controlled by storage control devices constituting a storage control layer operatively coupled to the physical storage devices and hosts. The storage control layer includes a first virtual layer interfacing with the hosts, operable to represent a logical address space available to said hosts and characterized by an Internal Virtual Address Space (IVAS); a second virtual layer characterized by a Physical Virtual Address Space (PVAS), interfacing with the physical storage devices, and operable to represent an available storage space; and an allocation module operatively coupled to the first and second virtual layers and providing mapping between IVAP and PVAS. Each address in PVAS is configured to have a corresponding address in IVAS. The allocation module facilitates management of IVAS and PVAS, enabling separation of a process of deleting certain logical object into processes performing changes in IVAS and PVAS, respectively.

Abstract: A storage system and method are provided including physical storage devices controlled by storage control devices constituting a storage control layer operatively coupled to the physical storage devices and hosts. The storage control layer includes: a first virtual layer interfacing with the hosts, operable to represent a logical address space characterized by logical block addresses, characterized by an Internal Virtual Address Space (IVAS) and operable, responsive to I/O requests addressed to logical block addresses, to provide protocol-dependent translation of said logical block addresses into IVAS addresses; and a second virtual layer interfacing with the physical storage space, and operable to represent available physical space to said hosts and characterized by a Physical Virtual Address Space (PVAS). Each address in PVAS having a corresponding address in IVAS.

Abstract: A storage system and method is provided including physical storage devices controlled by storage control devices constituting a storage control layer operatively coupled to the physical storage devices and hosts. The storage control layer includes: a first virtual layer interfacing with the hosts, operable to represent a logical address space characterized by logical block addresses and available to said hosts and characterized by an Internal Virtual Address Space (IVAS) and operable, responsive to a configuration or I/O request addressed to the logical block addresses, to translate said logical block addresses into IVAS addresses; and a second virtual layer interfacing with the physical storage devices, operable to represent an available physical space to said hosts and characterized by a Physical Virtual Address Space (PVAS), addresses in PVAS having corresponding address in IVAS. The second virtual layer is operable to translate said respective IVAS addresses into addresses in the physical address space.

Abstract: Storage systems with reduced energy consumption, methods of operating thereof, corresponding computer program products and corresponding program storage devices. Some non-limiting examples of a write method include: configuring a plurality of storage disk units such that at any given point in time there are at least two storage disk drives operating in active state in any storage disk unit; caching in a cache memory one or more write requests and generating a consolidated write request corresponding to a stripe in a RAID group; destaging the consolidated write request; and writing the destaged consolidated write request in a write out of place manner to one or more storage disk drives operating at the destage point of time in active state.

Abstract: There is provided a storage system comprising a plurality of disk units adapted to store data at respective ranges of logical block addresses (LBAs), said addresses constituting an entire address space, and a storage control grid operatively connected to the plurality of disk units and comprising a plurality of data servers, each server comprising operatively coupled cache memory and non-volatile memory.

Abstract: Establishing a plurality of storage areas includes associating each of a first plurality of storage areas of a first type that contain sections of data with corresponding ones of second plurality of storage areas of a second type having pointers to alternative sections of data storage areas of the first type, where initially none of the second plurality of storage areas is available for accessing data corresponding thereto, and, after associating all of the first and second plurality of storage areas, activating the second plurality of storage areas to make the second plurality of storage areas available for accessing data. Exclusive access may be enabled for all of the first plurality of storage areas prior to activating the second plurality of storage areas or to each storage area one at a time.

Abstract: There are provided a storage system, storage control unit and method of operating thereof. A storage system comprises a permanent storage subsystem comprising a first cache memory and a non-volatile storage medium, and a storage control unit operatively coupled to said subsystem and to a second cache memory operable to cache “dirty” data pending to be written to the permanent storage subsystem and to enable, responsive to at least one command by the control storage unit, destaging said “dirty” data or part thereof to the permanent storage subsystem.

Abstract: There are provides an allocation module and a method of allocating a logical disk to a next member of a given RAID group. The method comprises: identifying one or more physical disks comprising at least one logical disk with already allocated member of said given RAID group, thus giving rise to allocated physical disks; identifying one or more pairs constituted by at least one allocated physical disk with non-allocated physical disks, said pairs having minimal number of RAID groups with members allocated to both physical disks in the pair, thus giving rise to a first group of pairs with minimal contention value; and selecting among the first group of pairs with minimal contention value one or more non-allocated physical disks as candidate physical disks for allocating said next member MEMi+1 of said given RAID group, wherein 0<i<N+1.

Abstract: There are provided a storage system and a method of operating thereof. The method comprises: caching in the cache memory a plurality of data portions matching a certain criterion, thereby giving rise to the cached data portions; analyzing the succession of logical addresses characterizing the cached data portions; if the cached data portions cannot constitute a group of N contiguous data portions, where N is the number of RG members, generating a virtual stripe being a concatenation of N data portions wherein at least one data portion among said data portions is non-contiguous with respect to any other portion in the virtual stripe, and wherein the size of the virtual stripe is equal to the size of the stripe of the RAID group; destaging the virtual stripe and writing it to a respective storage device in a write-out-of-place manner. The virtual stripe can be generated responsive to receiving a write request from a client and/or responsive to receiving a write instruction from a background process.

Abstract: There are provided a storage system and a method of operating thereof. The method comprises: a) representing to a plurality of hosts an available logical address space divided into one or more logical groups (e.g. logical volumes, virtual partitions, snapshots, combinations of a given logical volume and its respective snapshot(s), etc.), and b) mapping between one or more contiguous ranges of addresses related to the logical address space and one or more contiguous ranges of addresses related to the physical address space, wherein said mapping is provided with the help of one or more mapping trees, each tree assigned to a separate logical group in the logical address space.