Dell Products Inc.

Emc IP Holding Company LLC

Oran Baruch

Vamsi K Vankamamidi

Maor Rahamim

Alexander Shknevsky

Ronen Gazit

Ajay Karri

Jenny Derzhavetz

Michael Litvak

Kurt W Everson

Techniques of the present disclosure can include: identifying blocks of storage available for allocation; generating a list denoting an allocation order of storage chunks of the blocks; receiving a write I/O operation that writes data to a first logical address; allocating a storage chunk in accordance with the allocation order of the list, wherein a first block includes the storage chunk and a second storage chunk; storing the first data in the storage chunk of the first block; removing the second storage chunk from the list; and creating a mapping between the first logical address and the first block indicating the second storage chunk is reserved for storing content written to a logical address included in a volume logical address range comprising the first logical address. The allocation order can spread allocation distance between blocks and chunks of the same block to avoid contention during flushes.

Storage allocation techniques for large writes using list formed from each block

For a flush request for a first block of user data directly stored into a physical block of non-volatile data storage, allocating a virtual layer block, and storing, in the virtual layer block, a first set of virtual block pointers indicating pages of the first block within the physical block. Pointers to the virtual block pointers in the first set are then stored into a leaf layer of a logical address mapping tree. The virtual layer block is identified for a subsequent flush request issued for a second block of user data directly stored into the physical block, and a second set of virtual block pointers indicating pages of the second block within the physical block is stored in the virtual layer block. Pointers to the virtual block pointers in the second set are stored into a leaf layer node of another logical address mapping tree.

Flushing directly ingested user data

Techniques for limiting or reducing storage accessibility 'hiccups' in active-active clustered systems that perform large writes. The techniques can include executing, by a surviving, failover, or rebooted node of an active-active clustered system, a specialized recovery protocol that includes treating each large write request from a host computer as a plurality of small write requests while execution of the specialized recovery protocol is in progress, draining all dedicated sub-ubers for a primary and secondary node of the active-active clustered system, and, having completed execution of the specialized recovery protocol, resuming normal treatment of large write requests from the host computer. In this way, the need and complexity of managing large writes and maintaining their corresponding sub-uber information during recovery from a forced reboot, crash, or disaster involving the primary or secondary node can be avoided, and storage accessibility hiccups due to performing the large writes can be limited or reduced.

Low hiccup time fail-back in active-active dual-node storage systems with large writes

A method, computer program product, and computing system for sensing a failure within a system within a computing device. The system may include a cache memory system and a vaulted memory comprising a random access memory (RAM) having a plurality of independent persistent areas. A primary node and secondary node may be provided. The primary node may occupy a first independent persistent area of the RAM of the vaulted memory. The secondary node may occupy a second independent persistent area of the RAM of the vaulted memory. Data within the vaulted memory may be written to a persistent media using an iterator. The data may include at least one dirty page. Writing data within the vaulted memory to the persistent media may include flushing the at least one dirty page to the persistent media.

Storage system and method using persistent memory

A technique of managing writes in a data storage system includes receiving I/O requests specifying data to be written, storing a set of the data to be written in an extent of a data log, and preventing data reduction from being performed on the set of data in the extent for at least a specified time interval, said time interval enabling portions of the set of data to be overwritten with new data and rendering data reduction of such portions unnecessary.

Avoiding data reduction debt for quickly overwritten data

A method, computer program product, and computing system for generating a plurality of page buffers from a log memory system of the storage system using a persistent memory organization policy. A plurality of physical layer blocks (PLBs) are generated from the log memory system using the persistent memory organization policy. A set of page buffers are allocated from the plurality of page buffers to a first mapping page of a plurality of mapping pages. A PLB is allocated from the plurality of PLBs to a second mapping page of the plurality of mapping pages. One or more IO requests are processed using one or more of the first mapping page and the second mapping page.

System and method for flushing data using mapping page ownership

When a host I/O request is received, logging each transaction that is to be performed to process the host I/O request includes selecting from between a first persistent storage and a second persistent storage to identify the location to which the transaction is to be logged, and then logging the transaction to the selected location. The selection may be made based on a log policy indicating percentages of transactions to be logged to each of the first persistent storage and the second persistent storage. The percentages may be calculated periodically based on a dynamically measured performance characteristic of the first data storage, such as latency. All transactions for host I/O requests below a threshold minimum size, and/or all transactions for host I/O requests received while the current system throughput is below a minimum system throughput, may be logged to the first persistent storage.

Growing community of inventors

Tel Aviv, Israel

Oran Baruch