Emc IP Holding Company LLC

Dell Products Inc.

Geng Han

Jian Gao

Jibing Dong

Xinlei Xu

Hongpo Gao

Shaoqin Gong

Jianbin Kang

Jamin Jianbin Kang

Yousheng Liu

Lifeng Yang

Vamsi K Vankamamidi

Vladimir Shveidel

Baote Zhuo

Philippe Armangau

Changyu Feng

Huibing Xiao

Ruiyong Jia

Wayne Li

Shuyu Lee

Ilya Usvyatsky

Chun Ma

Liam Xiongcheng Li

Xiaobo Zhang

Ree Sun

Tao Chen

Xiongcheng Li

Haiying Tang

Michael P Wahl

Lili Chen

Uri Shabi

Lei Sun

Socheavy D Heng

Lester Zhang

Rongrong Shang

Bing Liu

Chen Gong

Naizhong Chiu

Haiyun Bao

Leon Zhang

Weihua Li

Sheng Wang

Peter Puhov

Tao Xu

Sihang Xia

Qingyun Liu

Tianshu Sun

Ping Ge

Shuai Ni

Amitai Alkalay

Ashok Tamilarasan

Ajay Karri

Robert Foley

Yingying Song

Ronald D Proulx

Vikram A Prabhakar

Denny Dengyu Wang

Zhenhua Zhao

Huadong Li

Zhihui Qiu

Joe Jian Liu

Charles Ma

Changrui Shao

Amit Zaitman

Vikram Prabhakar

Wenxuan Yin

Sun Ree

A method of data deduplication during log flushing includes use of an in-memory deduplication index as a cached sub-set of entries from a full on-drive deduplication index. In a pre-flush process, the data is scanned and the on-drive index is accessed to identify matching deduplication entries, and identified entries are copied into the in-memory index. The subsequent flush includes, for each data unit, (1) accessing the in-memory index to identify a matching deduplication entry for the data unit, (2) upon identifying a matching entry, storing the data unit in a deduplicated manner as a reference to previously stored data, and (3) upon not identifying a matching entry, storing the data unit in a non-deduplicated manner including a new data instance, without accessing the on-drive index. Performance and efficiency are improved by accessing only the in-memory index and avoiding the penalties of accessing the on-drive index.

Data storage system with streamlined deduplication during write log flushing

A method, computer program product, and computing system for generating a plurality of artificial storage devices for a storage system, wherein each artificial storage device includes a defined storage capacity. A total useable storage capacity for the storage system is defined based upon, at least in part, the defined storage capacity for each artificial storage device and a storage capacity associated with a plurality of physical storage devices. One or more input/output (IO) requests are processed on the storage system. An IO request concerning an artificial storage device of the plurality of artificial storage devices is discarded.

System and method for simulating large capacity configurations in storage systems

Techniques for processing write conflicts involve determining, in response to receiving a write operation for a stripe, a state of a backend operation of a stripe set, wherein the backend operation includes one of a rebuilding or re-striping operation. The techniques further involve stopping the write operation in response to the state of the backend operation indicating that the backend operation is being executed in the stripe. The techniques further involve executing the write operation in response to the state of the backend operation indicating that the backend operation is not being executed in the stripe. Accordingly, write conflicts between a write operation and a backend operation for the same stripe can be favorably avoided, and concurrent execution of the write operation and the backend operation simultaneously for the same stripe is prevented, thus preventing the deterioration of a storage system and improving storage system security and stability.

Method, device, and computer program product for processing write conflicts

Nodes in a storage system can autonomously ingest I/O requests and flush data to storage. First and second nodes determine a sequence separator, the sequence separator corresponding to an entry in a page descriptor ring that separates two flushing work sets (FWS). The first node receives an input/output (I/O) request and allocates a sequence identification (ID) number to the I/O request. The first node determines a FWS for the I/O request based on the sequence separator and the sequence ID number, and commits the I/O request using the sequence ID number. The I/O request and the sequence ID number are sent to the second node.

Autonomous I/O ingestion and data flushing among nodes in storage systems

Logical address slices and corresponding metadata pages of mapping information can be partitioned into sets. Each node can be assigned exclusive ownership of one of the sets. In at least one embodiment, for a read I/O which is received at a first node and directed to a logical address LAthat is owned by a second node, the first node can request that the second owning node perform resolution processing for LA. The second node can own both LAand corresponding metadata pages included in mapping information used to map LAto a corresponding physical location PAincluding content Cstored at LA. The second node can perform resolution processing for LAusing the metadata pages corresponding to LAto either read and return Cto the first node, or obtain and return PAto the first node where the first node can then read Cdirectly using PA

Exclusive ownership of logical address slices and associated metadata

In at least one embodiment, processing can include: receiving write operations; persistently recording, in a write cache or log, the write operations using page descriptors (PDESCs) of a PDESC pool and page buffers (PBs) of a PB pool; selecting, in accordance with criteria, write data pages stored in the PB pool for demotion to a physical large block (PLB) pool included in backend non-volatile storage, wherein each write data page selected denotes content written by a corresponding one of the write operations; responsive to the selecting, persistently storing the write data pages of the PB pool in the PLB pool; and updating PDESCs associated with the write data pages to reference corresponding storage locations in the PLB pool rather than in the PB pool.

Techniques for extending a write cache

A method, computer program product, and computing system for monitoring data reduction information concerning a plurality of containers from a flush working set within a log memory system of a storage system, wherein the plurality of containers are associated with a storage object. An assigned working set size may be determined for a flusher based upon, at least in part, the data reduction information. The assigned working set may be generated for the flusher by adding one or more containers from the flush working set to the assigned working set based upon, at least in part, the assigned working set size. The one or more containers may be flushed, using the flusher, from the assigned working set to persistent memory within the storage system.

Storage and method for adaptive flushing in log structured storage systems

Techniques lock a storage area in a storage system including a first storage node and a second storage node. Such techniques involve adjusting a value of at least one of a first counter at the first node and a second counter at the second node in response to receiving a data access request for the storage area at at least one of the first node and the second node. Such techniques further involve allocating a lock flag to the first node in response to a ratio of the value of the first counter to the value of the second counter being greater than a first threshold, the lock flag indicating that the storage area is locked by the first node. Accordingly, storage resources required by nodes that are accessed more frequently in statistics are effectively reduced, and the efficiency of applying stripe lock reduction are improved.

Method, device and computer program product for locking a storage area in a storage system

Techniques for accessing data involve reading data from at least one disk among a plurality of disks. Such techniques further involve detecting whether a lookup table stored on a memory is empty, where the lookup table stores information indicating data loss. Such techniques further involve comparing, in response to the lookup table not being empty, data read information associated with the read data with table items in the lookup table to determine whether there is a table item in the lookup table that matches the data read information. Such techniques further involve sending, in response to determining that there is a table item that matches the data read information, the information indicating data loss. Such a technique improve the efficiency of data access, reduces the complexity of the system and the power consumption of the system, and improves the performance of the system.

Method, electronic device, and computer program product for accessing data of raid

A method, computer program product, and computing system for processing, using a storage node, one or more updates to one or more metadata pages of a multi-node storage system. The one or more updates may be stored in one or more data containers in a cache memory system of the storage node, thus defining an active working set of data containers. Flushing ownership for each data container of the active working set may be assigned to one of the storage nodes based upon an assigned flushing ownership for each data container of a frozen working set and a number of updates within the frozen working set processed by each storage node, thus defining an assigned flushing storage node for each data container of the active working set. The one or more updates may be flushed, using the assigned flushing storage node, to a storage array.

System and method for multi-node storage system flushing

A method, computer program product, and computer system for permitting, by a computing device, entering of a barrier object of a plurality of barrier objects with a first set of one or more Application Programming Interfaces (APIs) only when the barrier object is not set. The first set of the one or more APIs on the barrier object may wait until the barrier object is reset. A second set of the one or more APIs may set the barrier object. Waiting may occur until there are no longer any flows in the barrier object.

System and method for efficient snapshots barrier mechanism for system with presorted container-based log

A method, computer program product, and computing system for defining one or more user data portions and at least two reserved portions of a solid-state drive (SSD). An operating mode of the SSD may be determined. One or more of the at least two reserved portions of the SSD may be utilized based upon, at least in part, the operating mode of the SSD.

Storage management system and method

Implementations of the present disclosure relate to method and device for managing a storage system. The method comprises in response to receiving a write request at a storage system, determining whether storage units allocated to a logic storage unit of the storage system are sufficient for data associated with the write request. The method also comprises in response to determining that the allocated storage units are insufficient, allocating a new storage unit to the logic storage unit. The method further comprises updating metadata associated with allocation of the storage units of the storage system, the metadata indicating a mapping between the logic storage unit and the storage units. The method also comprises encrypting the updated metadata. Other implementations of the present disclosure also involve corresponding method, device and computer-readable medium for decryption metadata and recovering the logic storage unit using the decrypted metadata.

Method and device for managing storage system

A protocol for processing write operations can include recording each write operation in a log using a PDESC (page descriptor)-PB (page block) pair. The log entry for the write operation can be included in a container of logged writes. In a dual node system, the protocol when processing the write operation, that writes first data, can include incrementing a corresponding one of two counters of the container, where the corresponding counter is associated with one of the system's nodes which received the write operation and and caches the first data. Each container can be associated with an logical block address (LBA) range of a logical device, where logged writes that write to target addresses in the particular LBA range are included in the container. Nodes can independently determine flush ownership using the container's counters and can flush containers based on the flush ownership.

Container flush ownership assignment

Embodiments of the present disclosure relate to a method, an electronic device, and a computer program product for managing a storage system. The method includes: determining, at a first device of the storage system, whether a load of a first accelerator resource of the first device exceeds a load threshold; sending, if it is determined that the load exceeds the load threshold, a job processing request to a second device in a candidate device list to cause the second device to process a target job of the first device using a second accelerator resource of the second device, the candidate device list indicating devices in the storage system that can be used to assist the first device in job processing; receiving, from the second device, latency information related to remote processing latency of processing the target job using the second accelerator resource; and updating the candidate device list based on the latency information. The embodiments of the present disclosure can optimize the system performance.

Method, device, and computer program product for managing storage system

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Beijing, China

Geng Han