Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include storing one or more data volumes to a small computer system interface storage device, and receiving a request to map a given data volume to a host computer. One or more attributes of the given data volume are identified, and using the identified one or more attributes, a unique logical unit number (LUN) for the given data volume is generated. The given data volume is mapped to the host computer via the unique LUN. In some embodiments, the generated LUN includes one of the one or more attributes. In additional embodiments, the generated LUN includes a result of a hash function using the one or more attributes. In storage virtualization environments, the data volume may include secondary logical units, and mapping the given data volume to the host may include binding the SLU to the host.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include storing one or more data volumes to a small computer system interface storage device, and receiving a request to map a given data volume to a host computer. One or more attributes of the given data volume are identified, and using the identified one or more attributes, a unique logical unit number (LUN) for the given data volume is generated. The given data volume is mapped to the host computer via the unique LUN. In some embodiments, the generated LUN includes one of the one or more attributes. In additional embodiments, the generated LUN includes a result of a hash function using the one or more attributes. In storage virtualization environments, the data volume may include secondary logical units, and mapping the given data volume to the host may include binding the SLU to the host.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include storing one or more data volumes to a small computer system interface storage device, and receiving a request to map a given data volume to a host computer. One or more attributes of the given data volume are identified, and using the identified one or more attributes, a unique logical unit number (LUN) for the given data volume is generated. The given data volume is mapped to the host computer via the unique LUN. In some embodiments, the generated LUN includes one of the one or more attributes. In additional embodiments, the generated LUN includes a result of a hash function using the one or more attributes. In storage virtualization environments, the data volume may include secondary logical units, and mapping the given data volume to the host may include binding the SLU to the host.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include storing one or more data volumes to a small computer system interface storage device, and receiving a request to map a given data volume to a host computer. One or more attributes of the given data volume are identified, and using the identified one or more attributes, a unique logical unit number (LUN) for the given data volume is generated. The given data volume is mapped to the host computer via the unique LUN. In some embodiments, the generated LUN includes one of the one or more attributes. In additional embodiments, the generated LUN includes a result of a hash function using the one or more attributes. In storage virtualization environments, the data volume may include secondary logical units, and mapping the given data volume to the host may include binding the SLU to the host.

Abstract: A fast snapshot is configured to determine if a snapshot is utilized for asynchronous mirroring. The fast snapshot operation is performed by avoiding reference counts of the one or more data units associated with the snapshot from being updated at a creation time and a deletion time when the snapshot is utilized for asynchronous mirroring.

Abstract: A fast snapshot is configured to store a state of a computing environment at a point in time. The fast snapshot operation is performed by avoiding reference counts of one or more data units associated with the snapshot from being updated at a creation and a deletion time.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include conveying first data from local regions of a local volume of a local storage system to a remote storage system having a remote volume with remote regions in a one-to-one correspondence with the local regions. While conveying the first data, a request is received to update a given local region, and the given local region is marked.

Abstract: Methods, apparatus and computer program products for a distributed system include dividing logical volume data into data subsets, and defining at least one distributedly storage configuration for the logical volume. Metadata for the logical volume is written to a first set of first metadata tables, and the first set of first metadata tables is divided into metadata subsets having a one-to-one correspondence with the data subsets. The metadata subsets are distributed among the multiple digital information devices, and the metadata is copied from the first set of first metadata tables to a second set of corresponding second metadata tables in a one-to-one correspondence with the first metadata tables, and the second metadata tables are distributed among the multiple digital information devices.

Abstract: Methods, apparatus and computer program products for a distributed system include dividing logical volume data into data subsets, and defining at least one distributedly storage configuration for the logical volume. Metadata for the logical volume is written to a first set of first metadata tables, and the first set of first metadata tables is divided into metadata subsets having a one-to-one correspondence with the data subsets. The metadata subsets are distributed among the multiple digital information devices, and the metadata is copied from the first set of first metadata tables to a second set of corresponding second metadata tables in a one-to-one correspondence with the first metadata tables.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include defining a source data volume including a first multiple of source snapshots, and storing the first multiple of the source snapshots in a first storage pool including a second multiple of storage regions having respective identifiers. Upon receiving a request to copy the source data volume to a target data volume in a second storage pool, a first given source snapshot including a first set of the storage regions is accessed, and a second given source snapshot preceding the first given source snapshot is identified, the second given source snapshot including a second set of the storage regions. A set difference of the second and the first sets of the storage regions is identified, and respective identifiers of the set difference are stored to the target volume.

Abstract: A method includes receiving data objects for storage in at least one or more first storage devices characterized by a first write endurance, and one or more second storage devices characterized by a second write endurance that is lower than the first write endurance. Respective write-activity levels are estimated for the data objects. For each data object, a choice is made whether to store the data object in the first storage devices or in the second storage devices based on an estimated write-activity level of the data object. The data object is stored in the chosen storage devices.

Abstract: A method for data storage includes running on multiple interconnected compute nodes respective virtual heads that collaboratively store files in persistent storage. In response to receiving in an initiator virtual head a request to write at least a portion of a given file, the initiator virtual head selects one or more destination virtual heads for storing the portion. The portion is sent from the initiator virtual head to the selected destination virtual heads, and a notification of the selected destination virtual heads is sent to an owner virtual head, which has been assigned to own metadata of the portion. In the destination virtual heads, the portion received from the initiator virtual head is cached, and committed to the persistent storage only in response to receiving a commit instruction from the owner virtual head.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that enable a computer to receive a request to allocate one or more logical regions to a logical volume, and to verify, in response to the request, an availability on one or more storage devices of a number of physical regions corresponding to the one or more requested logical regions. In response to the verification, the one or more logical regions can be activated for write operations to a cache, so that any data written to the logical regions is stored to the cache. Subsequent to activating the one or more logical regions, one or more actual physical regions can be allocated to the logical volume. Upon allocating the one or more actual physical regions, any data stored in the cache can be destaged to the one or more actual physical regions.

Abstract: A method includes receiving data objects for storage in at least one or more first storage devices characterized by a first write endurance, and one or more second storage devices characterized by a second write endurance that is lower than the first write endurance. Respective write-activity levels are estimated for the data objects. For each data object, a choice is made whether to store the data object in the first storage devices or in the second storage devices based on an estimated write-activity level of the data object. The data object is stored in the chosen storage devices.

Abstract: A method for data storage includes running on multiple interconnected compute nodes respective virtual heads that collaboratively store files in persistent storage. In response to receiving in an initiator virtual head a request to write at least a portion of a given file, the initiator virtual head selects one or more destination virtual heads for storing the portion. The portion is sent from the initiator virtual head to the selected destination virtual heads, and a notification of the selected destination virtual heads is sent to an owner virtual head, which has been assigned to own metadata of the portion. In the destination virtual heads, the portion received from the initiator virtual head is cached, and committed to the persistent storage only in response to receiving a commit instruction from the owner virtual head.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include defining a source data volume including a first multiple of source snapshots, and storing the first multiple of the source snapshots in a first storage pool including a second multiple of storage regions having respective identifiers. Upon receiving a request to copy the source data volume to a target data volume in a second storage pool, a first given source snapshot including a first set of the storage regions is accessed, and a second given source snapshot preceding the first given source snapshot is identified, the second given source snapshot including a second set of the storage regions. A set difference of the second and the first sets of the storage regions is identified, and respective identifiers of the set difference are stored to the target volume.

Abstract: Methods, apparatus and computer program products implement embodiments of the present invention that include defining a source data volume including a first multiple of source snapshots, and storing the first multiple of the source snapshots in a first storage pool including a second multiple of storage regions having respective identifiers. Upon receiving a request to copy the source data volume to a target data volume in a second storage pool, a first given source snapshot including a first set of the storage regions is accessed, and a second given source snapshot preceding the first given source snapshot is identified, the second given source snapshot including a second set of the storage regions. A set difference of the second and the first sets of the storage regions is identified, respective identifiers of the set difference are stored to the target volume, and a target snapshot is created for the target volume.

Abstract: A fast snapshot is configured to store a state of a computing environment at a point in time. The fast snapshot operation is performed by avoiding reference counts of one or more data units associated with the snapshot from being updated at a creation and a deletion time.

Abstract: A fast snapshot is configured to determine if a snapshot is utilized for asynchronous mirroring. The fast snapshot operation is performed by avoiding reference counts of the one or more data units associated with the snapshot from being updated at a creation time and a deletion time when the snapshot is utilized for asynchronous mirroring.

Abstract: A fast snapshot is configured to store a state of a computing environment at a point in time. The fast snapshot operation is performed by avoiding reference counts of one or more data units associated with the snapshot from being updated at a creation and a deletion time.