Abstract: Techniques for optimizing data storage are disclosed herein. In particular, methods and systems for implementing redundancy encoding schemes with data storage systems are described. The redundancy encoding schemes may be scheduled according to system and data characteristics. The schemes may span multiple tiers or layers of a storage system. The schemes may be generated, for example, in accordance with a transaction rate requirement, a data durability requirement or in the context of the age of the stored data. The schemes may be designed to rectify entropy-related effects upon data storage. The schemes may include one or more erasure codes or erasure coding schemes. Additionally, methods and systems for improving and/or accounting for failure correlation of various components of the storage system, including that of storage devices such as hard disk drives, are described.

Abstract: Techniques for optimizing data storage are disclosed herein. In particular, methods and systems for implementing redundancy encoding schemes with data storage systems are described. The redundancy encoding schemes may be scheduled according to system and data characteristics. The schemes may span multiple tiers or layers of a storage system. The schemes may be generated, for example, in accordance with a transaction rate requirement, a data durability requirement or in the context of the age of the stored data. The schemes may be designed to rectify entropy-related effects upon data storage. The schemes may include one or more erasure codes or erasure coding schemes. Additionally, methods and systems for improving and/or accounting for failure correlation of various components of the storage system, including that of storage devices such as hard disk drives, are described.

Abstract: Methods and systems are provided herein that facilitate cost-effective, scalable and reliable archival data organization and management. In an embodiment, data are redundantly encoded and stored to provide data reliability. Further, encoded data may be stored in self-describing storage entities that provide information describing data stored therein. Information provided by self-describing storage entities may be used to construct a limited map that is usable to facilitate data placement and data location services during data storage and retrieval. Data reliability and durability is provided because information about data stored in the system is mostly contained in the storage entities themselves. Cost efficiency is provided because only a limited map is provided for efficiency purposes instead of a potentially large global index data structure.

Abstract: In this disclosure, a resource scheduler is described that allows virtual machine instances to earn resource credits during the low activity levels. Virtual machine instances that spend a predominant amount of time operating at low activity levels are able to quickly gain resource credits. Once these virtual machine instances acquire enough resource credits to surpass a threshold level, the resource scheduler can assign a high priority level to the virtual machine instances that provide them with priority access to CPU resources. The next time that the virtual machine instances enter a high activity level, they have a high priority level that allows them to preempt other, lower priority virtual machine instances. Thus, these virtual machine instances are able to process operations and/or respond to user requests with low latency.

Abstract: In response to receiving a request from a client to store an object, a key-durable storage system may assign the object to a volume in its data store, generate a key for the object (e.g., an opaque identifier that encodes information for locating the object in the data store), store the object on one disk in the assigned volume, store the key redundantly in the assigned volume (e.g., using a replication or erasure coding technique), and may return the key to the client. To retrieve the object, the client may send a request including the key, and the system may return the object to the client. If a disk fails, the system may determine which objects were lost, and may return the corresponding keys to the appropriate clients in a notification. The system may be used to back up a more expensive object-redundant storage system.

Abstract: A system for storing data includes a rack, one or more data storage drive assemblies coupled to the rack, and a data control module coupled to the rack. The data storage drive assemblies include one or more drive mechanical modules configured to store data and one or more drive control modules coupled to the drive mechanical modules. The drive control modules control mechanical operations in the drive mechanical modules. The drive mechanical modules and the associated drive control modules are separable from one another without removing the other module from the at least one data storage drive assembly.

Abstract: In this disclosure, a resource scheduler is described that allows virtual machine instances to earn resource credits during the low activity levels. Virtual machine instances that spend a predominant amount of time operating at low activity levels are able to quickly gain resource credits. Once these virtual machine instances acquire enough resource credits to surpass a threshold level, the resource scheduler can assign a high priority level to the virtual machine instances that provide them with priority access to CPU resources. The next time that the virtual machine instances enter a high activity level, they have a high priority level that allows them to preempt other, lower priority virtual machine instances. Thus, these virtual machine instances are able to process operations and/or respond to user requests with low latency.

Abstract: A system for storing data includes two or more drive mechanical modules configured to store data, one or more drive control modules coupled to the drive mechanical modules, and a data control module. The drive control modules control mechanical operations in the drive mechanical modules. The data control modules access data on the drive mechanical modules.

Abstract: Techniques for optimizing data storage are disclosed herein. In particular, methods and systems for implementing redundancy encoding schemes with data storage systems are described. The redundancy encoding schemes may be scheduled according to system and data characteristics. The schemes may span multiple tiers or layers of a storage system. The schemes may be generated, for example, in accordance with a transaction rate requirement, a data durability requirement or in the context of the age of the stored data. The schemes may be designed to rectify entropy-related effects upon data storage. The schemes may include one or more erasure codes or erasure coding schemes. Additionally, methods and systems for improving and/or accounting for failure correlation of various components of the storage system, including that of storage devices such as hard disk drives, are described.

Abstract: Techniques for optimizing data storage are disclosed herein. In particular, methods and systems for implementing redundancy encoding schemes with data storage systems are described. The redundancy encoding schemes may be scheduled according to system and data characteristics. The schemes may span multiple tiers or layers of a storage system. The schemes may be generated, for example, in accordance with a transaction rate requirement, a data durability requirement or in the context of the age of the stored data. The schemes may be designed to rectify entropy-related effects upon data storage. The schemes may include one or more erasure codes or erasure coding schemes. Additionally, methods and systems for improving and/or accounting for failure correlation of various components of the storage system, including that of storage devices such as hard disk drives, are described.

Abstract: Embodiments of the present disclosure are directed to, among other things, validating the integrity of received and/or stored data payloads. In some examples, a storage service may perform a first partitioning of a data object into first partitions based at least in part on a first operation. The storage service may also verify the data object, by utilizing a verification algorithm, to generate a first verification value. In some cases, the storage service may additionally perform a second partitioning of the data object into second partitions based at least in part on a second operation. The second partitions may be different from the first partitions. Additionally, the archival data storage service may verify the data object using the verification algorithm to generate a second verification value. Further, the storage service may determine whether the second verification value equals the first verification value.

Abstract: Techniques for optimizing data storage are disclosed herein. In particular, methods and systems for implementing redundancy encoding schemes with data storage systems are described. The redundancy encoding schemes may be scheduled according to system and data characteristics. The schemes may span multiple tiers or layers of a storage system. The schemes may be generated, for example, in accordance with a transaction rate requirement, a data durability requirement or in the context of the age of the stored data. The schemes may be designed to rectify entropy-related effects upon data storage. The schemes may include one or more erasure codes or erasure coding schemes. Additionally, methods and systems for improving and/or accounting for failure correlation of various components of the storage system, including that of storage devices such as hard disk drives, are described.

Abstract: Technologies are described herein for ensuring data in long-term storage will be accessible at a future date. Upon storing the data in long-term storage, a well-defined instance of data processing resources is created on a host computing platform for the installation and testing of a related application that is capable of accessing the stored data. Once testing of the related application is complete, a machine image is generated from the instance and stored with the data in the long-term storage. If access to the data stored in the long-term storage is required at a future date, the data and associated machine image may be retrieved, and a compatible instance of data processing resources created in which the machine image may be restored. The data in the long-term storage may then be accessed by the related applications executing in the newly created instance.

Abstract: In a system in which documents are generated dynamically in response to user requests, historical data is collected regarding data retrieval subtasks, such as service requests, that are performed to generate such documents. This data is used to predict the specific subtasks that will be performed to respond to specific document requests, such that these subtasks may be initiated preemptively at or near the outset of the associated document generation task. In one embodiment, the historical data is included within, or is used to generate, a mapping table that maps document generation tasks (which may correspond to specific URLs) to the data retrieval subtasks that are frequently performed within such tasks.

Abstract: An application programming interface for a data storage service provides a convenient mechanism for clients of the data storage service to access its various capabilities. An API call may be made to initiate a job and in response a job identifier may be provided. A separate API call specifying the job identifier may be made and a response providing information related to the job may result. Various API calls may be used to store data, retrieve data, obtain an inventory of stored data, and to obtain other information relating to stored data.

Abstract: A cost-effective, durable and scalable archival data storage system is provided herein that allow customers to store, retrieve and delete archival data objects, among other operations. For data storage, in an embodiment, the system stores data in a transient data store and provides a data object identifier may be used by subsequent requests. For data retrieval, in an embodiment, the system creates a job corresponding to the data retrieval and provides a job identifier associated with the created job. Once the job is executed, data retrieved is provided in a transient data store to enable customer download. In various embodiments, jobs associated with storage, retrieval and deletion are scheduled and executed using various optimization techniques such as load balancing, batch processed and partitioning. Data is redundantly encoded and stored in self-describing storage entities increasing reliability while reducing storage costs. Data integrity is ensured by integrity checks along data paths.

Abstract: Methods and systems are provided herein that facilitate cost-effective and reliable data identification in an archival data storage system. In an embodiment, a data object stored in an archival data storage system is identified by a data object identifier which encodes storage location information that may be used to locate a data object stored in an archival data storage system that reduces the cost to store a global index. The data object identifier may also encode policy information such as access control information usable for validating subsequent access to the data object, payload validation information such as size and digest usable for verifying the integrity of the payload data, metadata validation information such as error-detection codes usable for validating integrity of the data object identifier and other information.

Abstract: Embodiments of the present disclosure are directed to, among other things, managing power of one or more data storage devices. In some examples, a storage service may obtain a schedule associated with enabling different storage devices at different times. The storage service may also identify a request of a batch of requests for accessing the storage devices. In some cases, the storage service may also determine which storage device to activate based at least in part on the schedule and/or the request. Further, the storage service may manage power of a storage device based at least in part on the determination of which storage device to activate.

Abstract: Embodiments of the present disclosure are directed to, among other things, validating the integrity of received and/or stored data payloads. In some examples, a storage service may perform a first partitioning of a data object into first partitions based at least in part on a first operation. The storage service may also verify the data object, by utilizing a verification algorithm, to generate a first verification value. In some cases, the storage service may additionally perform a second partitioning of the data object into second partitions based at least in part on a second operation. The second partitions may be different from the first partitions. Additionally, the archival data storage service may verify the data object using the verification algorithm to generate a second verification value. Further, the storage service may determine whether the second verification value equals the first verification value.

Abstract: In a system in which documents are generated dynamically in response to user requests, historical data is collected regarding data retrieval subtasks, such as service requests, that are performed to generate such documents. This data is used to predict the specific subtasks that will be performed to respond to specific document requests, such that these subtasks may be initiated preemptively at or near the outset of the associated document generation task. A subtask that would ordinarily be postponed pending the outcome of a prior subtask can thereby be performed in parallel with the prior subtask, reducing document generation times. In one embodiment, the historical data is included within, or is used to generate, a mapping table that maps document generation tasks (which may correspond to specific URLs) to the data retrieval subtasks that are frequently performed within such tasks.