Seagate Technology Incorporated

Dot Hill Systems Corporation

Michael David Barrell

Zachary David Traut

Ian Davies

Douglas William Dewey

Kenneth F Day, Iii

Phillip Raymond Colline

Ritvik Viswanatha

Adithya Uligere Narasimhamurthy

Mohamad H El-Batal

George Alexander Kalwitz

Thomas George Wicklund

Stephen S Huh

Richard O Weiss

Christopher B Tumblin

Scott Gergely

Jess Lacy

A method for mitigating the effects of malware is provided. The method includes determining a compressibility of a portion of data, determining a data corruption condition is satisfied based on the determined compressibility, and modifying a retention policy for retention of stored snapshots associated with the portion of data based on the satisfaction of the data corruption condition. The modifying of the retention policy includes generating a first snapshot associated with the portion of the data, prior to writing cached data associated with the portion of the data, writing the cached data associated with the portion of the data, and generating a second snapshot associated with the portion of the data, responsive to the deletion.

Malware mitigating storage controller

A data storage system can have one or more hosts connected to a data storage subsystem with the host having a host processor and the data storage subsystem having a controller. Write back data generated at the host triggers the host processor to allocate a cache location in the data storage subsystem where the generated data is subsequently stored. The generated write back data is written in a non-volatile destination address as directed by the controller prior to waiting for a secondary event with the generated data stored in both the cache location and the non-volatile destination address. Detection of the secondary event prompts the controller to signal the host processor that the cache location is free for new data.

Data storage system with write back cache

The presently disclosed technology is directed to combatting data theft, particularly of verified authentication data (or hashes thereof) such as login information, thumbprint data, digital signatures, identification numbers, and any other data that should be known to an accessor of stored data. The verified authentication data is initially saved for later comparison in a new type of memory, write-and-compare-only memory, where the data may be queried as to whether a to-be-verified value matches the stored verified value, but the stored and verified data is not read from the write-and-compare-only memory. This prevents a data breach by preventing the verified authentication data from being read by anyone, including those with access (whether legitimate or illegitimate) to any system connected to the write-and-compare-only memory.

Write and compare only data storage

Systems and processes are disclosed to preserve data integrity during a storage controller failure. In some examples, a storage controller of an active-active controller configuration can back-up data and corresponding cache elements to allow a surviving controller to construct a correct state of a failed controller's write cache. To accomplish this, the systems and processes can implement a relative time stamp for the cache elements that allow the backed-up data to be merged on a block-by-block basis.

Preserving data integrity during controller failures

Systems and methods are disclosed for multiple duration deduplication entries. A processor may be configured to perform data deduplication operations, including setting a first indicator for first metadata stored to a hash database identifying a first time interval to maintain the first metadata in the database, and setting a second indicator for second metadata stored to the database identifying a second time interval to maintain the second metadata in the database longer than the first time interval. The processor may remove the first metadata from the database when no duplicative data is detected for the first metadata within the first time interval, and remove the second metadata from the database when no duplicative data is detected for the second metadata within the second time interval.

Multiple duration deduplication entries

Preserving data integrity during controller failure

Use of a deduplication module remote from a storage system for storage of data subject to deduplication by the remote deduplication module. The storage system may generate a hash of target data and send the hash of the target data to the remote deduplication module. The remote deduplication module may access a hash database corresponding to the storage system and apply a deduplication algorithm on the hash. In turn, information regarding a deduplication result may be returned to the storage system which may either store the unique target data or update a mapping between the target data and duplicate existing data in a persistent storage of the storage device. The remote deduplication module may be executed by scalable cloud resources such that the computational resources dedicated to the deduplication module may be scaled.

Remote deduplication of data in a storage system

A data storage network may have multiple data storage devices that each consist of a device buffer. A network buffer and buffer circuit can be found in a network controller with the buffer circuit arranged to divide and store data associated with a data access request in the network buffer and the device buffer of the first data storage device.

Network data storage buffer system

A system includes a memory and a processor coupled to the memory, where the processor is configured to perform various operations. The operations include receiving, in response to a first read input/output operation, a first location of a first data block. The operations also include executing the first read input/output operation at the first data block at the first location. The operations also include selecting a second location within a first search range for destaging a second data block based at least in part on the first location. The operations also include destaging the second data block at the second location upon a determination that a second read input/output operation is not currently executing or queued for execution.

Localized data block destaging

A data storage system includes a host system configured to provide an I/O request stream and a data storage subsystem. The data storage subsystem has a data storage device and a processor. The processor is configured to provide streaming data in response to the I/O request stream, determine a current streaming rate of the I/O request stream, and determine a time-based read ahead size based on a time ahead duration and the current streaming rate of the I/O request stream. The time-based read ahead size may be updated while streaming, for example, after a delay period.

Data storage systems using time-based read ahead

A plurality of stripe zones are mapped across drives in an array. A capacity of each of the stripe zones is smaller than or equal to an average size of the drives. A failed drive is determined in the array. A deletable stripe zone is selected that is being used for user data storage. The deletable stripe zone is taken offline and used to rebuild a subset of the plurality of the stripe zones affected by the failed drive.

Using deletable user data storage space to recover from drive array failure

An apparatus may include a controller configured search a hash database storing entries corresponding to hash values of previously stored data to find a hash page of the hash database corresponding to a range of hash values including the first hash value. When the hash page is found, the controller may be configured to determine whether the hash page does not include an entry for the first hash value, the first hash page further including a base hash value for the range of hash values. When the hash page does not include an entry for the first hash value, the controller may be configured to generate a first entry of the first hash page for the first hash value, the first entry including an offset value from the base hash value corresponding to the first hash value and a data location at which the received data is to be stored.

Deduplication database management

Implementations described and claimed herein provide a method and system for managing execution of commands for a storage device, the method comprising identifying individual streams processing read ahead operations in a storage controller, determining an amount of read ahead data that each individual stream is processing in the read ahead operations, determining a total amount of read cache available for the storage controller, and determining a total amount of read ahead data that all the individual streams are processing in the read ahead operations.

Read ahead management in a multi-stream workload

Implementations described and claimed herein provide a method and system for detecting slow storage drives. In one implementation, the method includes dynamically creating a storage drive peer group including a plurality of storage drives, comparing performance statistics of the storage drives in the storage drive peer group, selecting an outlier storage drive of the storage drive peer group based on the comparison of the performance statistics, passively monitoring response times of the storage drives in the storage drive peer group, comparing average response times of the storage drives in the storage drive peer group, flagging an outlier storage drive of the storage drive peer group with an outlier storage drive designation responsive to comparison of the average response times, actively measuring workload metrics of the outlier storage drive, comparing workload metrics data of the outlier storage drive to workload metrics reference data, and performing a remedial action.

Slow drive detection

A plurality of arrays of storage devices, each providing dual storage device redundancy, is provided. The plurality of arrays of storage devices includes a plurality of mirrored sets of primary storage devices, each including an even number of at least two or more primary storage devices. Each of the mirrored sets of primary storage devices stores a first and a second copy of data. The plurality of arrays of storage devices also includes a secondary storage device, which is a single physical storage device that stores a third copy of the data stored on each of the plurality of mirrored sets of primary storage devices. The secondary storage device has at least the capacity to store the data stored on the plurality of mirrored sets of primary storage devices. Dual storage device redundancy preserves data if data cannot be read from one or two physical storage devices in any array.

Growing community of inventors

Longmont, CO, United States of America

Michael David Barrell