Patent application number | Description | Published |
20080313496 | Gracefully degradable versioned storage systems - Multiple versions of data on different sets of machines allow a system to degrade gracefully even when experiencing excessive failures. When excessive failures cause the latest versions to be unavailable, the system becomes degraded, but still offers an old version if available. A most recent coherent set of the available older versions is found and provided. The degree of degradation increases gradually as the system experiences more and more failures. Graceful degradation is desirably complementary to fault tolerance. | 12-18-2008 |
20100106753 | CYCLIC COMMIT TRANSACTION PROTOCOL - A cyclic commit protocol is used to store relationships between transactions and is used by the technology to determine whether a transaction is committed or not. The protocol allows creation of a cycle of transactions which can be used to recover the state of a storage device after a host failure by identifying the last committed version of intention records as committed or uncommitted based on the data stored in the physical pages. | 04-29-2010 |
20100262752 | STORAGE VIRTUAL CONTAINERS - A controller of a Solid State Device (SSD) defines a mapping from memory devices, such as flash packages, that make up the SSD to one or more storage virtual containers. The storage virtual containers are exposed to an operating system by the controller through an interface. The operating system may then make operation requests to the one or more storage virtual containers, and the controller may use the mapping to fulfill the operation requests from the corresponding flash packages. The storage virtual containers are mapped to the flash packages to take advantage of the parallelism of the flash packages in the SSD so that the controller may fulfill operation requests received from the operating system in parallel. | 10-14-2010 |
20110067030 | FLOW BASED SCHEDULING - A job scheduler may schedule concurrent distributed jobs in a computer cluster by assigning tasks from the running jobs to compute nodes while balancing fairness with efficiency. Determining which tasks to assign to the compute nodes may be performed using a network flow graph. The weights on at least some of the edges of the graph encode data locality, and the capacities provide constraints that ensure fairness. A min-cost flow technique may be used to perform an assignment of the tasks represented by the network flow graph. Thus, online task scheduling with locality may be mapped onto a network flow graph, which in turn may be used to determine a scheduling assignment using min-cost flow techniques. The costs may encode data locality, fairness, and starvation-freedom. | 03-17-2011 |
20110138106 | EXTENDING SSD LIFETIME USING HYBRID STORAGE - A hybrid storage device uses a write cache such as a hard disk drive, for example, to cache data to a solid state drive (SSD). Data is logged sequentially to the write cache and later migrated to the SSD. The SSD is a primary storage that stores data permanently. The write cache is a persistent durable cache that may store data of disk write operations temporarily in a log structured fashion. A migration policy may be used to determine how long to cache the data in the write cache before migrating the data to the SDD. The migration policy may be implemented using one or more migration triggers that cause the contents of the write cache to be flushed to the SSD. Migration triggers may include a timeout trigger, a read threshold trigger, and a migration size trigger, for example. | 06-09-2011 |
20120226936 | DUPLICATE-AWARE DISK ARRAYS - A duplicate-aware disk array (DADA) leaves duplicated content on the disk array largely unmodified, instead of removing duplicated content, and then uses these duplicates to improve system performance, reliability, and availability of the disk array. Several implementations disclosed herein are directed to the selection of one duplicate from among a plurality of duplicates to act as the proxy for the other duplicates found in the disk array. Certain implementations disclosed herein are directed to scrubbing latent sector errors (LSEs) on duplicate-aware disk arrays. Other implementations are directed to disk reconstruction/recovery on duplicate-aware disk arrays. Yet other implementations are directed to load balancing on duplicate-aware disk arrays. | 09-06-2012 |
20130152057 | OPTIMIZING DATA PARTITIONING FOR DATA-PARALLEL COMPUTING - A data partitioning plan is automatically generated that—given a data-parallel program and a large input dataset, and without having to first run the program on the input dataset—substantially optimizes performance of the distributed execution system that explicitly measures and infers various properties of both data and computation to perform cost estimation and optimization. Estimation may comprise inferring the cost of a candidate data partitioning plan, and optimization may comprise generating an optimal partitioning plan based on the estimated costs of computation and input/output. | 06-13-2013 |
20140101225 | CONSISTENCY-BASED SERVICE-LEVEL AGREEMENTS IN CLOUD STORAGE ENVIRONMENTS - An application programming interface is provided that allows applications to assign multiple service-level agreements to their data transactions. The service-level agreements include latency bounds and consistency guarantees. The applications may assign utility values to each of the service-level agreements. A monitor component monitors the various replica nodes in a cloud storage system for latency and consistency, and when a transaction is received from an application, the monitor determines which of the replica nodes can likely fulfill the transaction in satisfaction of any of the service-level agreements. Where multiple service-level agreements can be satisfied, the replica node that can fulfill the transaction according to the service-level agreement with the greatest utility is selected. The application may be charged for the transaction based on the utility of the service-level agreement that was satisfied. | 04-10-2014 |