Abstract: A technique for managing host data in a data storage apparatus having a storage processor (SP) provides virtualized storage processors (VSPs) as substantially self-describing and independent entities. Each VSP has its own namespace, independent of the namespace of any other VSP. Each VSP also has its own network address. Hosts may thus access VSPs directly, without having to include path information relative to the SP on which the VSP is operated. VSPs can thus be moved from one physical SP to another with little or no disruption to hosts, which may continue to access the VSPs on the new SPs using the same paths as were used when the VSPs were running on the original SPs.

Abstract: A technique operable in a data storage system performs initialization of storage structures in multiple stages and allows hosts to request access to a data object even when some of the storage structures supporting the data object have not been initialized. Rather than initializing all storage structures for a data object before allowing host access, a storage processor instead initializes only a protocol stub structure. The protocol stub structure is configured to receive protocol requests from hosts and to initiate further processing should a storage request in that protocol be received. The further processing includes, in response to receiving a protocol request directed to a host-accessible data object, identifying storage structures involved in processing that protocol request and directing the storage processor to initialize those storage structures.

Abstract: A technique for replicating a file from a source data storage system (source) to a destination data storage system (destination) includes receiving, by the destination from the source, (i) file data for multiple logical extents of the file and (ii) respective tiering metadata for those logical extents. The destination selects, based on the tiering metadata, one or more storage tiers available on the destination. The destination updates a local replica of the file by placing the logical extents on the selected tier or tiers.

Abstract: An improved technique involves providing file system shrink capability by shrinking the size of the volume file in which an upper deck file system is stored. Along these lines, a data storage system, upon receiving a request to shrink an upper deck file system, determines a new address in the upper deck file system, based on an amount the upper deck file system is to be shrunk, to which the end-of-file (EOF) pointer of the volume file will point. The new address will have a smaller distance from the address of the file pointer than the original address to which the EOF pointer points. The data storage system then identifies nonempty data blocks of the upper deck file system that have logical addresses having a larger distance from the address of the file pointer than the second logical address.

Abstract: A method includes (a) receiving a command to create an upper-deck filesystem of a specified size, the upper-deck filesystem residing within a logical volume expressed from a container file of a lower-deck filesystem, (b) provisioning a plurality of storage provisioning units (SPUs) from a storage pool of the data storage system to the container file in an order reflecting proximity of the SPUs within storage devices of the data storage system, the plurality of SPUs providing storage for the entire container file, and (c) subsequent to provisioning the plurality of SPUs to the container file, executing a plurality of threads in parallel to write metadata of the upper-deck filesystem to the plurality of SPUs, representing the upper-deck filesystem. Other embodiments are directed to a system, a computerized apparatus, and a computer program product for performing methods similar to that described above.

Abstract: Embodiments are directed to methods for allowing an I/O path of a data storage system to directly modify an object model while bypassing the highly-contested transaction lock used by a control path. This may be done by introducing a local lock to be used for individual resources within the object model. The control path also uses this local lock mechanism (in the context of a transaction lock) for essential resources that might be accessed by the I/O path in order to avoid accessing a given essential resource at the same time as the I/O path. A data storage system, apparatus, and computer program product for performing similar methods are also provided.

Abstract: A technique performs replication. The technique involves receiving, by processing circuitry, a virtual storage processor (VSP) replication command from a user. The VSP replication command specifies a source VSP and a destination VSP (e.g., configuration data which defines an operating environment). The technique further involves identifying, by the processing circuitry and in response to the VSP replication command, multiple source data objects which are configured to store data from the context of the source VSP. The technique further involves automatically creating, after the multiple source data objects are identified, multiple replication sessions to replicate the multiple source data objects as multiple destination data objects which are configured to store data from the context of the destination VSP. Once created, the entire lifecycle of the replication session occurs at the VSP level and replication of the internals of the VSP are entirely hidden from the end user.

Abstract: A method, computer program product, and computing system for receiving a storage operation request for a logical storage object. A storage insurance value is associated with the logical storage object. The storage operation request is processed to associate a storage liability value with the storage operation request. Whether the storage operation request should be effectuated is determined based, at least in part, upon the storage liability value and the storage insurance value.

Abstract: A technique manages host data in a data storage array. The technique involves placing, in response to host input/output (I/O) requests from a set of host devices, host data in a container file system which is stored in a slice pool of storage slices (e.g., storage space of a standard size such as 256 MB) formed by multiple storage tiers of the data storage array. Each storage tier provides storage access at a different storage access speed. The technique further involves assigning classifications to storage slices of the slice pool which store the container file system, each classification being assigned based on storage slice access history resulting from the host I/O requests. The technique further involves relocating portions of the container file system among the multiple storage tiers according to the classifications assigned to the storage slices of the slice pool.

Abstract: A technique forms contents of a deduplication container from a standalone container file system stored on the same data storage array on which the deduplication container is stored. Such a standalone container includes a container file which is formed by standalone blocks that are not shared with any other file within the standalone container outside of snapshots of that file. The standalone blocks store host data and which are hierarchically related to each other. Upon receiving a deduplication command, the storage processor carries out a set of deduplication operations which include creating and storing the deduplication container in the data storage array. The deduplication container includes container files which are formed by deduplication blocks storing the host data and which are hierarchically related to each other.

Abstract: A technique for managing data storage operations in a data storage system having a file-based front end system and a block-based back end array includes provisioning a set of storage resources on the array for use exclusively with one or more virtualized storage processors (VSPs), where each VSP identifies multiple file systems. In response to a management command to perform a data storage operation on a VSP, the back-end array performs the specified operation on the provisioned set of storage resources. Thus, the back-end array performs the data operation exclusively on the VSP (or on multiple VSPs) and therefore on all of its constituent file systems as one.

Abstract: A method, computer program product, and computing system for defining a master slice pool within a backend storage array of a storage system. The master slice pool includes a plurality of data storage slices. A first portion of the plurality of data storage slices is assigned to a first frontend system included within the storage system, thus defining a first frontend slice pool. One or more data storage slices included within the first frontend slice pool are allocated to one or more storage objects associated with the first frontend system. A quantity of unused data storage slices included within the first frontend slice pool is determined. The quantity of unused data storage slices is adjusted based upon a target slice level.

Abstract: A technique provides mobility to VSPs. The technique involves receiving, by processing circuitry, a VSP move command from a user. The VSP move command specifies a source VSP and a destination. The technique further involves identifying, by the processing circuitry and in response to the VSP move command, multiple source data objects which are configured to store data from the context of the source VSP. The multiple source data objects reside in a source storage pool. The technique further involves, after the multiple source data objects are identified, transforming the multiple source data objects into multiple destination data objects which are configured to store data from the context of a destination VSP at the destination. The multiple destination data objects reside in a destination storage pool which is different from the source storage pool. Such operation effectively provides VSP migration from source to destination.

Abstract: A technique is used for optimizing data location in data storage arrays. A primary storage array is associated with a secondary storage array, the primary storage array and secondary storage array including auto-tiering functionality, where the secondary storage array is configured as a backup storage array for the primary storage array. Tiering metadata is derived for a storage object stored on the primary storage array. The tiering metadata is transmitted to the secondary storage array. Auto-tiering is initiated at the secondary storage array, where the received tiering metadata is provided as input to the secondary storage array's auto-tiering function when auto-tiering replicated storage object associated with the tiering metadata.

Abstract: A technique performs virtual storage processor (VSP) failover. The technique involves accessing, by a first physical storage processor of the data storage apparatus, a VSP to create an operating environment for a host file system from the first physical storage processor. The technique further involves, after accessing the VSP to create the operating environment for the host file system from the first physical storage processor, detecting a failure of the first physical storage processor. The technique further involves accessing, in response to detecting the failure of the first physical storage processor and by a second physical storage processor of the data storage apparatus, the VSP to re-create the operating environment for the host file system from the second physical storage processor.

Abstract: A technique for managing storage tiering in a data storage apparatus operates at a fine level of granularity in response to write requests as blocks are allocated for writing. As write requests arrive or are otherwise processed by the data storage apparatus, the data storage apparatus identifies a quality of service to be provided for satisfying each write request and allocates a set of blocks from storage devices of storage tiers that provide the identified quality of service. The data storage apparatus may then store the information specified in the write request in the newly allocated blocks.

Abstract: A method is used in managing storage space in storage systems. Metadata of a slice of a storage pool in a data storage system is evaluated for returning the slice as free storage to the storage pool. Based on the evaluation, returning of the slice to the storage pool is affected. The metadata of the slice indicates whether the slice includes user data.

Abstract: A data storage system includes storage devices and a processing subsystem executing software forming a lower-deck file system and an upper-deck file system. The lower-deck file system presents a volume file from which storage is provided to the upper-deck file system, and units of storage of the storage devices are allocable to the upper-deck file system but are not reserved to it. The volume file is thinly provisioned, and additional units of storage are added dynamically to increase its allocated size in response to demand from the upper-deck file system. The lower-deck file system operates in a mapped mode in which a block address in the lower-deck file system is obtained by a generally arbitrary mapping (e.g., an Inode/IB tree) of a block address in the volume file.

Abstract: A method and system for use in managing data storage is disclosed. Data storage in a data storage system is managed. The data storage system comprises a first data storage tier and a second data storage tier configured such that the performance characteristics associated with one of the data storage tiers is superior to the other data storage tier. I/O activity is determined in connection with a data group stored on one of the first and second data storage tiers. It is determined whether to migrate the data group stored on the one of the first and second data storage tiers to the other data storage tier based on the performance characteristics associated with the other data storage tier and the determined I/O activity. The data group is migrated to the other data storage tier in response to determining to migrate the data group to the other data storage tier.

Abstract: A technique provides virtual storage processor (VSP) mobility with induced file system format migration. The technique involves receiving a command specifying (i) a source VSP which includes source file systems which store data in a source file system format, (ii) a destination, and (iii) a destination file system format. The technique further involves forming, in response to the command, a destination VSP which includes destination file systems. The technique further involves copying, while the source VSP is accessed by a set of host computers, data from the source file systems of the source VSP to the destination file systems of the destination VSP. The destination file systems store the copied data in the destination file system format. The technique further involves synchronizing, after the data is copied from the source file systems to the destination file systems, state changes between the source VSP and the destination VSP.