Abstract: A request to write data corresponding to at least a first portion of a file is received. It is determined whether to perform the request either as an in-place write or as an out-of-place write. Performing the in-place write comprises performing a write to a low latency storage device, and performing the out-of-place write comprises performing a write to a higher latency storage device. The request is performed as either the in-place write or the out-of-place write based on the determination. Performing the request as the in-place write includes writing the data to a first location on a storage tier storing the first portion of the file, and performing the request as the out-of-place write includes writing the data to a second location on one of a plurality of storage tiers of a computing node, other than the first location.

Abstract: A size associated with a content file is determined to be greater than a threshold size. Contents of the content file split across a plurality of component files are stored. Metadata, for the content file, is updated to reference a plurality of component file metadata structures for the component files. A node of the metadata is configured to track different sizes of portions of the content file stored in different component files of the plurality of component files. File metadata of the content file is split across the plurality of component file metadata structures and each component file metadata structure of the plurality of component file metadata structures specifies a corresponding structure organizing data components for a corresponding portion of the content file.

Abstract: A method and system for managing a storage cluster is described. An identification of a plurality of nodes of a storage cluster to be removed from the storage cluster is received. It is determined whether to allow the removal of the plurality of nodes. In response to a determination that the removal of the plurality of nodes is allowed, identifications are made of data migrations to be performed to rebalance the data among nodes remaining in the storage cluster after removal of the plurality of nodes. The data migrations are performed. The plurality of nodes are removed from the storage cluster.

Abstract: A method and system for managing a storage cluster is described. An identification of a plurality of nodes of a storage cluster to be removed from the storage cluster is received. It is determined whether to allow the removal of the plurality of nodes. In response to a determination that the removal of the plurality of nodes is allowed, identifications are made of data migrations to be performed to rebalance the data among nodes remaining in the storage cluster after removal of the plurality of nodes. The data migrations are performed. The plurality of nodes are removed from the storage cluster.

Abstract: Techniques for cloning, writing to, and reading from file system metadata. Cloning involves identifying a first set of pointers included in a first root node in a file system metadata tree structure that stores file system metadata in leaf nodes of the tree structure, creating a first copy of the first root node that includes the first set of pointers, creating a second copy of the first root node that includes the first set of pointers, associating the first copy with a first view, and associating the second copy with a second view. Reading generally involves traversing the tree structure towards a target leaf node that contains data to be read. Writing generally involves traversing the tree structure in the same manner, but also creating copies of any nodes to be modified if those nodes are deemed to have a different treeID than a particular root node.

Abstract: File access statistics associated with a content file are maintained by a file tier agent of a secondary storage system. The content file is accessible via a primary storage system. A target storage tier corresponding to the file access statistics associated with the content file is determined according to one or more policies. At least a portion of data of the content file is migrated to the determined storage tier while accessibility of the content file via the primary storage system is maintained.

Abstract: A method and apparatus for maintaining file system consistency in a distributed system using version vectors is presented. A method generally includes comparing incarnation and transaction identifiers of a current version vector associated with a file with incarnation and transaction identifiers of a last completed version vector associated with the file. Upon determining that a current version vector reflects operations on the file that are either earlier than or the same as the identifiers in the last completed version vector, the node performing one or more file system operations on the file.

Abstract: A size associated with a content file is determined to be greater than a threshold size. In response to the determination, file metadata of the content file split and stored across a plurality of component file metadata structures. The file metadata of the content file specifies tree structure organizing data components of the content file and each component file metadata structure of the plurality of component file metadata structures stores a portion of the tree structure. A snapshot tree is updated to reference the plurality of component file metadata structures for the content file.

Abstract: A request to write data corresponding to at least a first portion of a file is received. It is determined whether to perform the request either as an in-place write or as an out-of-place write. Performing the in-place write comprises performing a write to a low latency storage device, and performing the out-of-place write comprises performing a write to a higher latency storage device. The request is performed as either the in-place write or the out-of-place write based on the determination. Performing the request as the in-place write includes writing the data to a first location on a storage tier storing the first portion of the file, and performing the request as the out-of-place write includes writing the data to a second location on one of a plurality of storage tiers of a computing node, other than the first location.

Abstract: Techniques for cloning, writing to, and reading from file system metadata. Cloning involves identifying a first set of pointers included in a first root node in a file system metadata tree structure that stores file system metadata n leaf nodes of the tree structure, creating a first copy of the first root node that includes the first set of pointers, creating a second copy of the first root node that includes the first set of pointers, associating the first copy with a first view, and associating the second copy with a second view. Reading generally involves traversing the tree structure towards a target leaf node that contains data to be read. Writing generally involves traversing the tree structure n the same manner, but also creating copies of any nodes to be modified if those nodes are deemed to have a different treeID than a particular root node.

Abstract: File access statistics associated with a content file are maintained by a file tier agent of a secondary storage system. The content file is accessible via a primary storage system. A target storage tier corresponding to the file access statistics associated with the content file is determined according to one or more policies. At least a portion of data of the content file is migrated to the determined storage tier while accessibility of the content file via the primary storage system is maintained.

Abstract: A method, a non-transitory computer-readable storage medium, and a computer system for managing bandwidth allocated to a virtual machine running on a host computer is disclosed. In an embodiment, a method involves obtaining the current bandwidth for a virtual machine running on a host computer, determining bandwidth demand for the virtual machine as a function of the current bandwidth and a growth margin, and adjusting a bandwidth cap for the virtual machine based on the determined bandwidth demand. In an embodiment, when applied, the technique allows for bandwidth to be allocated to the virtual machines without the sum of allocated bandwidth exceeding a global bandwidth cap.

Abstract: According to one embodiment of the present disclosure, a first set of file system objects included in performing a requested file system operation is identified in response to a request to perform a file system operation. An update intent corresponding to the requested file system operation is inserted into a data structure associated with each identified file system object. Each file system object corresponding to the corresponding data structure is modified as specified by the update intent in that data structure. After modifying the file system object corresponding to the corresponding data structure, the update intent is removed from that data structure.

Abstract: A management server and method for performing resource management operations in a distributed computer system takes into account information regarding multi-processor memory architectures of host computers of the distributed computer system, including information regarding Non-Uniform Memory Access (NUMA) architectures of at least some of the host computers, to make a placement recommendation to place a client in one of the host computers.

Abstract: System and method for performing resource allocation for a host computer cluster use resource allocation weight scores for resource nodes in a cluster resource allocation hierarchy of the host computer cluster based on the number of powered-on clients in the resource nodes.

Abstract: Embodiments described herein provide techniques for maintaining consistency in a distributed system (e.g., a distributed secondary storage system). According to one embodiment of the present disclosure, a first set of file system objects included in performing the requested file system operation is identified in response to a request to perform a file system operation. An update intent corresponding to the requested file system operation is inserted into an inode associated with each identified file system object. Each file system object corresponding to the inode is modified as specified by the update intent in that inode. After modifying the file system object corresponding to the inode, the update intent is removed from that inode.

Abstract: A technique for managing distributed computing resources in a virtual computing environment is disclosed. In an embodiment, a method includes receiving a recommended change to a virtual architecture of a virtual computing environment; determining an impact on current workload in the virtual computing environment if the recommended change is performed; determining an impact on future workload in the virtual computing environment if the recommended change is performed; calculating a combined impact on current and future workload; determining if the combined impact is above or below a threshold; if the combined impact on current and future workload is below the threshold, do not perform the recommended change; and if the combined impact on current and future workload is above the threshold, perform the recommended change.

Abstract: A management server and method for performing resource management operations in a distributed computer system takes into account information regarding multi-processor memory architectures of host computers of the distributed computer system, including information regarding Non-Uniform Memory Access (NUMA) architectures of at least some of the host computers, to make a placement recommendation to place a client in one of the host computers.

Abstract: A method of reducing power consumption of a server cluster of host systems with virtual machines executing on the host systems is provided. The method includes recommending host system power-on when there is a host system whose utilization is above a target utilization, and recommending host system power-off when there is a host system whose utilization is below the target utilization. Recommending host system power-on includes calculating impact of powering on a standby host system with respect to reducing the number of highly-utilized host systems in the server cluster. Recommending host system power-off includes calculating impact of powering off a host system with respect to decreasing the number of less-utilized host systems in the server cluster.

Abstract: A request to write data corresponding to at least a first portion of a file is received. It is determined whether to perform the request either as an in-place write or as an out-of-place write. Performing the in-place write comprises performing a write to a low latency storage device, and performing the out-of-place write comprises performing a write to a higher latency storage device. The request is performed as either the in-place write or the out-of-place write based on the determination. Performing the request as the in-place write includes writing the data to a first location on a storage tier storing the first portion of the file, and performing the request as the out-of-place write includes writing the data to a second location on one of a plurality of storage tiers of a computing node, other than the first location.