Abstract: A volume for object storage encompasses a single logical block address space and the first range of logical block addresses being within the single logical block address space. A first and second range of logical block addresses are initially allocated within the single logical block address space of the volume for storing respective object metadata and object data. One or both of the first and second ranges of logical block addresses are reallocated to increase storage utilized by one of the object metadata and the object data.

Abstract: A system includes multiple nodes that communicate among one another. Each of the multiple nodes includes at least one data storage container. The system also includes a sender sliding window (SSW) that controls sending of data from at least one node of the multiple nodes to at least one other node of the multiple nodes. The system further includes a receiver sliding window (RSW) that controls receiving of the data from the at least one node of the multiple nodes at the at least one other node of the multiple nodes. At least one of the SSW or the RSW is sharable amongst more than one node of the multiple nodes.

Abstract: A volume for object storage encompasses a single logical block address space and the first range of logical block addresses being within the single logical block address space. A first and second range of logical block addresses are initially allocated within the single logical block address space of the volume for storing respective object metadata and object data. One or both of the first and second ranges of logical block addresses are reallocated to increase storage utilized by one of the object metadata and the object data.

Abstract: Data access requests targeted to a distributed filesystem are tracked. The data access requests are distributed to different processes running on one more storage servers. For each of the processes, times of events within each of the processes is determined and the events are associated with an event identifier. Data may be stored that such as times of operations, event identifiers, and relationship data between the processes associated with the data access requests. The stored data characterizes different phases of the data access requests, which can be presented to a user for system analysis.

Abstract: A system includes multiple nodes that communicate among one another. Each of the multiple nodes includes at least one data storage container. The system also includes a sender sliding window (SSW) that controls sending of data from at least one node of the multiple nodes to at least one other node of the multiple nodes. The system further includes a receiver sliding window (RSW) that controls receiving of the data from the at least one node of the multiple nodes at the at least one other node of the multiple nodes. At least one of the SSW or the RSW is sharable amongst more than one node of the multiple nodes.

Abstract: A composite layout to store one or more extents of a data object in a first storage system and one or more extents of the data object in a second, different storage system. The first storage system may be configured for the efficient storage of small chunks of data such as, e.g., chunks of data small than the addressable block size of the storage devices used by the storage systems.

Abstract: A composite layout to store one or more extents of a data object in a first storage system and one or more extents of the data object in a second, different storage system. The first storage system may be configured for the efficient storage of small chunks of data such as, e.g., chunks of data small than the addressable block size of the storage devices used by the storage systems.

Abstract: Systems, apparatus, and methods for data distribution within a failure domain tree are described herein. Data objects may be distributed uniformly into symmetric failure domain trees. Asymmetric failure domain trees may be used to generate symmetric failure domain trees. The systems, apparatus, and methods may distribute a data object to attempt to satisfy the failure tolerance level of as many failure domain levels of the symmetric failure domain trees as possible.

Abstract: A system including a plurality of nodes. Each node includes a pending operations list, an unstable operations list, and a hardware controller. The pending operations list can include operations that have not yet been executed on the node. The unstable operations list can include operations that have not yet been stored on non-volatile data storage. Each of the operations listed in the unstable operations list can include a listing of all other operations that must be executed prior to the operation being executed on each respective node. The hardware controller can be configured to execute at least one operation listed in the pending operations list, remove at least one executed operation from the pending operations list, and remove at least one operation from the unstable operations list.

Abstract: A composite layout including a plurality of ranked sub-layouts may be used to provide various functionality for data object look-up and file system activities. Each sub-layout may include mapping information linking one or more extents of a data object to one or more locations on one or more storage apparatuses. Generally, mapping information in the highest priority sub-layout including mapped extents may be used during “reads” while the highest priority sub-layout may be used for “writes.

Abstract: A system utilizing elastic spares includes nodes and devices to store one or more data objects having information. The data object includes data object units each assigned to a storage location on a different node than the other units. The data object includes one or more spare units to store reconstructed information of a failed unit. When one of the data objects has a failed unit and no spare units available to store reconstructed information, a controller of the system assigns an elastic spare unit to an available storage location of one of the nodes. Reconstructed information of the failed unit is stored in the elastic spare unit.

Abstract: Systems, apparatus, and methods for data distribution within a failure domain tree are described herein. Data objects may be distributed uniformly into symmetric failure domain trees. Asymmetric failure domain trees may be used to generate symmetric failure domain trees. The systems, apparatus, and methods may distribute a data object to attempt to satisfy the failure tolerance level of as many failure domain levels of the symmetric failure domain trees as possible.

Abstract: A method of replicating a source file system on a storage system, the method including: utilising a changelog operable to store sequentially a data record corresponding to a modification of a source file system by a storage request; specifying a first data record of the changelog at a first time; initiating a scan of the directory inodes of the source file system at the first time; scanning the directory inodes; completing the scan at a second time later than the first time; specifying a second data record of the changelog at the second time; storing, in a database, information corresponding to the scanned directory inodes; updating the database with sequential data records from the first data record to the second data record of the changelog; and building, on a computer system, a replica target file system based on the database.

Abstract: A system including a plurality of nodes. Each node includes a pending operations list, an unstable operations list, and a hardware controller. The pending operations list can include operations that have not yet been executed on the node. The unstable operations list can include operations that have not yet been stored on non-volatile data storage. Each of the operations listed in the unstable operations list can include a listing of all other operations that must be executed prior to the operation being executed on each respective node. The hardware controller can be configured to execute at least one operation listed in the pending operations list, remove at least one executed operation from the pending operations list, and remove at least one operation from the unstable operations list.

Abstract: A system utilizing elastic spares includes nodes and devices to store one or more data objects having information. The data object includes data object units each assigned to a storage location on a different node than the other units. The data object includes one or more spare units to store reconstructed information of a failed unit. When one of the data objects has a failed unit and no spare units available to store reconstructed information, a controller of the system assigns an elastic spare unit to an available storage location of one of the nodes. Reconstructed information of the failed unit is stored in the elastic spare unit.

Abstract: A composite layout including a plurality of ranked sub-layouts may be used to provide various functionality for data object look-up and file system activities. Each sub-layout may include mapping information linking one or more extents of a data object to one or more locations on one or more storage apparatuses. Generally, mapping information in the highest priority sub-layout including mapped extents may be used during “reads” while the highest priority sub-layout may be used for “writes.

Abstract: In distributed state systems, server nodes can receive operation requests from multiple clients. When a server node executes an operation request, the server node can store an indicator of the operation request to a log of operations and send a reply message to the requesting client. The reply message can include a reply log having a list of N executed operation requests. If the server needs rebuilding, any operations not already stored to the server node log may be lost. The server can rebuild lost operations of a file system by receiving the reply logs or indicators of the operations therein from one or more clients.

Abstract: A method of replicating a source file system on a storage system, the method including: utilising a changelog operable to store sequentially a data record corresponding to a modification of a source file system by a storage request; specifying a first data record of the changelog at a first time; initiating a scan of the directory inodes of the source file system at the first time; scanning the directory inodes; completing the scan at a second time later than the first time; specifying a second data record of the changelog at the second time; storing, in a database, information corresponding to the scanned directory inodes; updating the database with sequential data records from the first data record to the second data record of the changelog; and building, on a computer system, a replica target file system based on the database.