Emc Corporation

Emc IP Holding Company LLC

Zvi Gabriel Benhanokh

Arieh Don

Philip Derbeko

Anat Eyal

Alex Veprinsky

Ran Margalit

Assaf Natanzon

Alexandr Veprinsky

Michael J Scharland

Orly Devor

Marik Marshak

Rong Yu

Eitan Bachmat

Stephen Richard Ives

Yaron Dar

Ishay Kedem

Ajith Balakrishnan

Qun Fan

Eitan Ben-Amos

William P Powers, Jr

Leonard R Linkens

Matthew Ivester

Example embodiments of the present invention relate to a method, an apparatus, and a computer program product for mirroring data in a data storage system across a first storage device having a first latency and a second storage device having a second latency. The method includes receiving an I/O at the data storage system and controlling the I/O to the first storage device having the first latency or the second storage device having the second latency according to properties of the I/O and properties of the first storage device having the first latency and the second storage device having the second latency.

Method and apparatus for asymmetric raid

Example embodiments of the present invention relate to a method, an apparatus, and a computer program product for directing I/Os for a chunk of data to a data storage system on which the chunk of data is stored. The host method includes receiving an I/O for a chunk of data, identifying to which data storage system the I/O should be sent to access the chunk of data, and sending the I/O for the chunk of data to the identified data storage system. Other example embodiments of the present invention relate to a method, an apparatus, and a computer program product for handling received I/Os during a migration of the chunk of data. The data storage system method includes migrating the chunk of data, queuing an I/O for the chunk of data received from a host during the migration, and rejecting the queued I/O as a result of the migration.

Method and system for using host driver for flexible allocation fast-sideways data movements

A computer-executable method, system, and computer program product for managing a flash cache module in a data storage system, wherein the data storage system is in communication with a data storage array, the computer-executable method comprising receiving a request to write a first data block to the flash cache module; analyzing the flash cache module to determine if there is a free portion of memory on the flash cache module for the first data block; and upon a negative determination, writing the first data block to a used portion of memory on the flash cache module.

Flash write amplification reduction

A method, computer program product, and computing system for processing one or more data chunks on a host server. The one or more data chunks are destined for storage within a portion of a data array coupled to the host server. The one or more data chunks are stored within a host cache system included within the host server. Storage criteria concerning the portion of a data array is reviewed. The storage criteria includes an array bandwidth allotment that defines a maximum bandwidth between the host server and the portion of the data array. The one or more data chunks are written to the portion of the data array based, at least in part, upon the storage criteria.

System and method for cache management

A method, computer program product, and computing system for storing a plurality of frontend data chunks within a cache system. The plurality of frontend data chunks correspond to a plurality of backend data chunks stored within a data array. A device weight is determined for each of the plurality of backend data chunks. The device weight is indicative of the type of storage device upon which each of the plurality of backend data chunks is stored within the data array. A deletion score is assigned to each of the plurality of frontend data chunks. Each deletion score is based, at least in part, upon the device weight determined for its corresponding backend data chunk.

System and method for caching data

A method, computer program product, and computing system for defining a portion of a frontend cache system for use as a data array cache portion. One or more cache slots included within a backend cache system are identified that are going to be overwritten with hot cache data and are currently filled with cold cache data. The cold cache data included within the one or more cache slots included within the backend cache system is written to one or more cache slots included within the data array cache portion.

Example embodiments of the present invention relate to a method and a system for improving performance of flash cache memory, such as in a host of a storage environment, for example, by preventing a cache cell from reaching an operation limit. The method includes determining that a number of operations to a first cell of a flash memory has reached a threshold and managing the flash memory according to the determination to prevent a failure of a second cell of the flash memory.

Method and apparatus for flash cache management

A computer-executable method, system, and computer program product for managing a data storage system, wherein the data storage system includes a host-cache and a data storage array, the computer-executable method, system, and computer program product comprising receiving an I/O request, processing the I/O request by locating data related to the I/O request and aligning the I/O request with the data to create an aligned portion of data, and updating the data storage array with the aligned portion of data.

System, apparatus, and method of automatic data padding

Example embodiments of the present invention relate to a method, an apparatus, and a computer program product for sending an I/O over a preferred path. The method includes determining a preferred path to an address range of a virtual storage unit striped across a plurality of disks of a data storage system and sending an I/O for data comprising the address range over the preferred path.

Method and apparatus for dynamic path-selection for improving I/O performance in virtual provisioned storage arrays with data striping

A method, computer program product, and computing system for monitoring data requests made by an application being executed on a host to generate a prediction concerning a quantity of data that may be needed by the application in the future. The quantity of data is stored within a backend cache system included within a data array coupled to the host. The quantity of data is provided to the host.

System and method for data prediction

A method, computer program product, and computing system for receiving an indication that a hard disk drive within a data array is failing, thus defining a failing hard disk drive. At least a portion of the data included within the failing hard disk drive is copied to a failover portion of a front end cache system included within a host coupled to the data array, thus defining a backup data set.

Described are techniques for representing and using RAID group consistency information. RAID group consistency information for a slice of data included on a device may be obtained by mapping the slice to an index. The index is one of a plurality of indices each associated with a structure indicating RAID group inconsistencies for a different portion of slices of data of the device. If the index is not associated with a structure, it may be determined that there is no RAID group inconsistency for the slice. If the index is associated with a structure, a hint bit associated with the slice may be determined wherein the hint bit encodes summary consistency information for a plurality of slices. A determination is made as to whether the hint bit is set, and, if the hint bit is not set, it is determined that there is no RAID group inconsistency for the slice.

Techniques for representing and storing RAID group consistency information

Embodiments of the invention exploit the fact that not all portions of a logical volume may include data written by a host. Accordingly, an embodiment of the invention includes setting a designated set of bits to 1 in a meta data table when a logical volume is initialized. These bits may be referred to herein as Never Written by Host (NWBH) bits. Separately, or in combination, an embodiment of the invention includes setting a NWBH bit to 0 when data is written to the associated portion of the logical volume. Separately, or in combination, an embodiment of the invention includes reading the NWBH bit upon receiving a read command associated with the associated portion of the logical volume. If the NWBH bit is equal to 1, data is not read from the associated portion of the logical volume; if the NWBH bit is equal to 0, data is read from the associated portion of the logical volume.

Growing community of inventors

Tel Aviv, Israel

Zvi Gabriel Benhanokh