Veritas Technologies LLC

Symantec Corporation

Satyendra Thakur

Suhas Ashok Dantkale

Kirubakaran Kaliannan

Prasad Vadlamannati

Yatin Nayak

Niranjan Sanjiv Pendharkar

Prasanta Ranjan Dash

Chaitanya Yalamanchili

Christopher Uhler

Shailesh Marathe

Prasanna V Wakhare

Rakesh Ranjan

A method of converting a data format in a storage system is provided. The method includes identifying a condition for when to make a data conversion from a write-optimized virtual disk format to a read-optimized virtual disk format; and locating, in response to the identified condition, a version of data. The method may include moving the version of data to a thin-provisioned format in-place virtual disk and detecting a set of overwrites from a remaining set of versions of the data, including blocks of data having been previously overwritten. The method may further include compacting each block within the set of overwrites to create a contiguous block such that an associated physical memory space is reclaimed, wherein the read-optimized virtual disk format of the data includes the thin-provisioned format in-place virtual disk and the contiguous block.

Policy and heuristic based conversion of write-optimized virtual disk format into read-optimized virtual disk format

The disclosed computer-implemented method for performing data replication in distributed cluster environments may include (1) identifying a distributed cluster environment that includes (A) a plurality of compute nodes that execute a plurality of virtual machines and (B) a data node that stores data that has been replicated from storage devices used by the virtual machines, (2) determining, at the data node, storage-utilization totals for the virtual machines that represent amounts of storage space on the storage devices used by the virtual machines, (3) identifying, based at least in part on the storage-utilization totals, a virtual machine whose storage-utilization total is highest among the plurality of virtual machines, (4) prioritizing the virtual machine and then in response to the prioritization, (5) directing the compute node to initiate a data replication process with the data node in connection with the virtual machine. Various other methods, systems, and computer-readable media are also disclosed.

Systems and methods for performing data replication in distributed cluster environments

A computer-implemented method for shipping I/O operations to prevent replication failure may include 1) attempting to perform an I/O operation in a system configured to replicate data from a data cluster to another data cluster, 2) detecting a failure in at least part of the attempt to perform the I/O operation that threatens to fail the system's replication of data from the data cluster to the other data cluster, and, in response to detecting the failure, 3) shipping the I/O operation from a node originally responsible for servicing the I/O operation to another node to complete the I/O operation without failing the system's replication of data from the data cluster to the other data cluster. Various other methods, systems, and computer-readable media are also disclosed.

Systems and methods for shipping an I/O operation to prevent replication failure

Write operations are scheduled for multiple nodes in a shared storage cluster that supports volume replication. Requests are received from nodes for allocation of space for write operations in a replication log. In response to a received request, the current capacity of the requesting node to manage a backlog can be determined. The amount of space in the replication log allocated to the node is then calibrated to the node's capacity, thereby preventing self-throttling. A separate priority can be assigned to each volume, and space in the replication log assigned to each volume based on its priority. Nodes can target synchronous and other latency sensitive operations to higher priority volumes. A single global queue can be maintained to schedule write operations for all nodes, thereby providing a fair scheduling. A separate local queue can be maintained for each node, thereby providing specific levels of preference to specific nodes.

I/O scheduling and load balancing across the multiple nodes of a clustered environment

A computer-implemented method for adding active volumes to existing replication configurations may include (1) identifying a new volume to be added to an existing replication configuration that replicates a plurality of volumes to a remote storage device, (2) using interchangeable bitmaps to perform an initial synchronization of the new volume with the remote storage device before replicating the new volume to the remote storage device as part of the existing replication configuration, (3) determining that a replication log associated with the replication configuration is capable of flagging future writes by the application to the new volume without overflowing, and, upon making that determination, (4) replicating the new volume to the remote storage device as part of the existing replication configuration. Various other methods, systems, and computer-readable media are also disclosed.

Systems and methods for adding active volumes to existing replication configurations

Various systems, methods, and processes to perform adaptive throttling of write operations in hybrid storage environments are disclosed. A credit value is assigned to a virtual machine. Input/output (I/O) operations generated by an application executing on the virtual machine are throttled based on the credit value assigned to the virtual machine. The credit value is assigned to the virtual machine in proportion to static measures and dynamic conditions. The static measures and the dynamic conditions are used to calculate a quality of service provided to the virtual machine by a storage system.

Adaptive throttling in hybrid storage environments

I/O scheduling and load balancing across the multiple nodes of a clustered environment using a single global queue

I/O scheduling and load balancing across the multiple nodes of a clustered environment utilizing data volume based scheduling priorities

A system and method for replaying writes in a replication log is provided. The replay of writes in the replication log can begin at some point after detecting an imminent overflow condition is detected. One method involves detecting the imminent overflow condition, performing a first synchronization for regions of the first volume based upon information in a first subset of the replication log, processing information in a second subset of the replication log while the first synchronization is ongoing, and performing a second synchronization for regions of the first volume based upon information in the second subset of the replication log, subsequent to the first synchronization and subsequent to processing the information in the second subset of the replication log.

Replay of writes in replication log

Systems and methods for shipping I/O operations to prevent replication failure

A computer-implemented method for natural batching of I/O operations on a replication log may include: 1) identifying a replication log that records the order of writes within a cluster replication system, 2) determining that the replication log is unavailable, 3) queuing incoming I/O operations for the replication log in a single batch while the replication log is unavailable, 4) determining that the replication log has become available, 5) ceasing queuing of incoming I/O operations for the replication log based on the determination that the replication log has become available, and 6) grouping a plurality of I/O operations in the single batch for processing in parallel by assigning a same generation number to the plurality of I/O operations. Various other methods, systems, and computer-readable media are also disclosed.

Growing community of inventors

Sunnyvale, CA, United States of America

Satyendra Thakur