Veritas Technologies LLC

Symantec Corporation

Freddy James

Anindya Banerjee

Mitul Kothari

Bhautik Patel

Kedar Shrikrishna Patwardhan

Brad Boyer

Ajay Salpekar

Sushil Sarjerao Patil

Madhav Buddhi

Edwin Menze

Anurag Vora

Rachit Chadha

Sudheer Keshav Chepa

Methods, computer program products, computer systems, and the like are disclosed that provide for the tracking of access patterns of inodes, and the issuing of inode read-ahead instructions, in order to pre-fetch inodes. Such a method can include, for example, identifying a unit of metadata in a file system, identifying a file system structure in the file system, determining whether a file structure of the file system structure is non-sequential, and, in response to a determination that the file structure is non-sequential, retrieving a list of units of metadata. In such embodiments, the file system structure is associated with the unit of metadata, and the determining includes accessing the file system structure. Further, in certain embodiments, the units of metadata identified in the list of units of metadata are stored in a storage device of the computer system.

Tracking access pattern of inodes and pre-fetching inodes

Disclosed herein are methods, systems, and processes to track access patterns of inodes, and to issue read-ahead instructions to pre-fetch inodes into memory. A location of a unit of metadata in a metadata storage area is determined. Another location in the metadata storage area that corresponds to a current metadata read operation is determined. Whether a metadata read-ahead operation can be performed is determined using the location of the unit of metadata and the another location. In response to a determination that the metadata read-ahead operation can be performed, the metadata-ahead operation is issued.

The disclosed computer-implemented method for delayed allocation in cluster storage may include (i) delegating, to a node attached to a storage cluster including one or more storage devices that include a group of allocation units, a subset of allocation units on the storage cluster to be held as a delayed allocation pool, (ii) receiving, from the node, a request to allocate allocation units on the storage cluster, (iii) deducting the number of allocation units from available allocation units in the delayed allocation pool, (iv) satisfying the allocation request by allocating allocation units not in the delayed allocation pool before allocating allocation units included in the delayed allocation pool, and (v) recalculating, based on the number of allocation units in the delayed allocation pool used to satisfy the allocation request, the number of available allocation units in the delayed allocation pool. Various other methods, systems, and computer-readable media are also disclosed.

Systems and methods for delayed allocation in cluster storage

The disclosed computer-implemented method for efficiently moving data within a filesystem may include (1) partitioning, on a storage device, physical address space of a filesystem into a plurality of logical partitions, (2) allocating, on the storage device, at least one container of data block identifiers representing data blocks for each of the logical partitions, (3) maintaining, on the storage device, a partition map of values identifying the container of data block identifiers, the logical partitions, and at least one offset associated with each of the logical partitions, (4) sending, on the storage device, the data blocks from a source logical partition within the logical partitions to a target logical partition within the logical partitions, and (5) updating, on the storage device, the partition map based on the data blocks sent from the source logical partition to the target logical partition. Various other methods, systems, and computer-readable media are also disclosed.

Systems and methods for efficiently moving data within a filesystem

Disclosed herein are methods, systems, and processes track access patterns of inodes, and to issue read-ahead instructions to pre-fetch inodes into memory. An inode is accessed and a directory of the inode is determined. Also determined is whether an entry for the directory exists in a global inode list. If the entry exists in the global inode list, whether a file structure of the directory is sequential or non-sequential is determined. If the entry does not exist in the global inode list, a new entry for the directory is added in the global inode list.

Various systems and methods use advisory metadata to track the status of file system objects. For example, one method can involve accessing a first item of advisory metadata, which is associated with a namespace-visible parent directory and identifies a first transaction and a first time, and accessing a second item of advisory metadata, which is also associated with the namespace-visible parent directory and identifies a second transaction and a second time. The namespace visible parent directory includes multiple namespace-hidden directories. The method can then select a time value of the advisory metadata for the namespace-visible parent directory, based upon the first item and the second item. The method can be performed by a computing device implementing a file system.

Timestamp handling for partitioned directories

Systems and methods for inode use are presented. In one embodiment; an inode reuse method includes: receiving an indication of an operation that involves access to file related information; assigning an inode to the access; identifying one of a plurality of inode reuse scenarios for the inode; and making the inode available for reuse in accordance with the one of the plurality of inode reuse scenarios. In one embodiment, the one of the plurality of inode reuse scenarios is a relatively expedited reuse scenario. In one exemplary implementation, the relatively expedited inode reuse scenario is utilized if the inode is not required for further processing associated with the operation. The inode can be reused for another immediately subsequent operation. In one embodiment, a first one of the plurality of inode reuse scenarios includes placing the inode at a head queue position of a use queue and a second one of the plurality of inode reuse scenarios includes placing the inode in a tail queue position of the use queue. Association of the inode to the inode reuse scenario can be tracked. The tracking can include flagging the inode for relatively expedited reuse.

Growing community of inventors

Kerala, India

Freddy James