Abstract: Technologies directed to a slot antenna as a calibration antenna for a phased array antenna are described. A communication system includes an antenna array with a first antenna module with a plurality of antenna elements and a conductive wall structure isolating each of the plurality of antenna elements. The conductive wall structure includes a portion separating a first antenna element and a second antenna element of the plurality of antenna elements. The portion includes a slot antenna.

Abstract: A selection to use a customer-generated matchmaking algorithm is received, by a multi-tenant gaming service, from a first customer. Indications of a plurality of video game player matchmaking requests and corresponding player characteristic data are provided, by the multi-tenant gaming service, for processing by the customer-generated matchmaking algorithm. An indication of a first player match determined by the customer-generated matchmaking algorithm, based on the video game player matchmaking requests and the player characteristic data, is received, by the multi-tenant gaming service. The first player match may be between at least a first player and a second player. Execution of a first video game session to which the first player and the second player are connected is hosted, by the multi-tenant gaming service.

Abstract: Methods, systems, and computer-readable media for energy-optimizing placement of resources in data centers are disclosed. A resource placement manager determines information descriptive of energy usage by one or more data centers. The one or more data centers comprise a plurality of computing resources in a plurality of corresponding locations. The resource placement manager selects, from the plurality of computing resources in the plurality of corresponding locations, a particular computing resource in a particular location for performing one or more computing tasks. The particular computing resource in the particular location is selected based at least in part on reducing energy usage associated with the one or more data centers according to the information descriptive of energy usage. The particular computing resource in the particular location is used to perform the one or more computing tasks.

Abstract: In one example, an apparatus comprises: a local on-chip memory; a computation engine configured to generate local data and to store the local data at the local on-chip memory; and a controller. The apparatus is configured to be coupled with a second device via an interconnect, the second device comprising a local memory. The controller is configured to: fetch the local data from the local on-chip memory; fetch remote data generated by another device from a local off-chip memory; generate output data based on combining the local data and the remote data; and store, via the interconnect, the output data at the local memory of the second device.

Abstract: Systems and methods are described for providing auxiliary functions in an on-demand code execution system in a manner that enables efficient execution of code. A user may generate a task on the system by submitting code. The system may determine the auxiliary functions that the submitted code may require when executed on the system, and may provide these auxiliary functions by provisioning or configuring sidecar virtualized execution environments that work in conjunction with the main virtualized execution environment executing the submitted code. Sidecar virtualized execution environments may be identified and obtained from a library of preconfigured sidecar virtualized execution environments, or a sidecar agent that provides the auxiliary function may be identified from a library, and then a virtualized execution environment may be provisioned with the agent and/or configured to work in conjunction with the main virtualized execution environment.

Abstract: An acceleration engine with multiple accelerators may share a common set of data that is used by each accelerator to perform computations on input data. The set of shared data can be loaded into the acceleration engine from an external memory. Instead of accessing the external memory multiple times to load the set of shared data into each accelerator, the external memory can be accessed once using direct memory access to load the set of shared data into the first accelerator. The set of shared data can then be serially loaded from one accelerator to the next accelerator in the acceleration engine using direct memory access. To achieve data parallelism and reduce computation time, a runtime driver may split the input data into data batches, and each accelerator can perform computations on a different batch of input data with the common set of shared data.

Abstract: Systems and methods are described for controlled migration of workloads between cell systems arranged in a cell-based architecture. Each cell system can implement a portion of an overall workload of the architecture, which may represent a network-accessible service. The isolation provided by cells may prevent widespread problems at the service, but may also conceal errors that might occur should workloads between the cells be redistributed. Such redistribution is often forced at inopportune moments, such as when a cell of the service has already failed. Systems and methods described herein enable detection of such errors by repeatedly migrating portions of workloads between cells. The system can monitor health information during or between migrations to ensure continued health of the service. If the service appears to be unhealthy after a migration, future migrations can be halted to enable a cause of the unhealthy state to be identified and rectified.

Abstract: Systems and methods are disclosed to implement, in a multi-writer database system, a database engine node that optimistically sends queued purge operations to a backend storage system without waiting for acknowledgement of previous operations from the storage system. If a conflict is later detected for a particular operation, the database engine node may retry some portion of the purge operations in the queue. In embodiments, the purge operations are performed as part of a garbage collection phase of a multi-version concurrency control (MVCC) protocol, where unneeded versions of objects previously generated for isolated snapshots are deleted. In embodiments, the operations in the queue may be grouped so that a rejection of one operation in the group will cause the entire group to be retried. Because these purge operations are idempotent and directed to objects that are invisible, they may be freely retried in arbitrary order, without maintaining any rollback state.

Abstract: At a first layer of an echo canceler, a first compensation for a first set of properties of output of an audio capture device of a first communication environment is applied. The first set of properties includes a property resulting from a difference in clock speeds of an audio capture device and an audio rendering device of the first communication environment. At a second layer of the echo canceler, at which output of the first layer is received, a second compensation for a second set of properties of the output of the first layer is applied. The second set of properties includes an echo. Applying the compensations comprises modifying neural network weights. Output of the second layer is transmitted to a second communication environment.

Abstract: Managed materialized views may be generated from across heterogeneous data sources. A request to create a materialized view may be received and performed by a materialized view management platform, which may obtain and generate the materialized view from different data sources and store the materialized view in a target system. Changes to the data sources may be obtained at the materialized view management platform and updates to the materialized view may be determined. The materialized view in the target system may be updated.

Abstract: Techniques for multi-stream transactional event processing under ACID semantics in a distributed log-based append-only datastore are described. A transaction coordinator writes events that are part of a transaction to a transaction buffer, where the events can be made visible to clients involved in the transaction while other clients are not aware. Upon committing the transaction, an optimistic concurrency control based technique is utilized to attempt to obtain locks on all events involved in the transaction across one or multiple shards by one or multiple designated writer nodes. When all involved writer nodes indicate that they are able to commit their events, the transaction can be committed.

Abstract: Described is a multiple-camera system and process for re-identifying an agent located in a materials handling facility based on anterior views of agents. An anterior view of a newly detected agent may be partitioned and color signatures generated for each partition. Likewise, stored anterior views of agents (candidate agents) that may potentially be the newly detected agent are partitioned and color signatures generated for each partition. Based on the color signatures, a similarity between the anterior view of the newly detected agent and the candidate agents is determined. The similarity may be used to either determine that the newly detected agent is one of the candidate agents or reduce the set of candidate agents that are considered during a manual review.

Abstract: A simulation environment (e.g., multi-player game) hosted by a provider network may implement componentized entities to reduce the amount of resource usage for a simulation (e.g., by reducing the amount of input/state data transmitted through the use of dynamically changing input structures). A user may add or remove any number of components to an entity that is simulated at the local client device. When inputs are received for one or more components, values for predictive states are locally determined for each component. An input packet is generated and sent to the provider network, which includes the inputs as well as data that is based on the values for the locally predicted states (e.g., a fingerprint or other unique ID). If necessary, a correction packet may be generated at the provider network and sent back to the client.

Abstract: Methods, systems, and computer-readable media for dynamic prefetching for database queries are disclosed. A query of a database is started according to a first prefetch policy. Before completing the query, the first prefetch policy is changed to a second prefetch policy. A portion of the query is performed according to the second prefetch policy.

Abstract: A hierarchical embedding model is used to obtain respective language-agnostic embeddings of entity records of a cross-language data set. A plurality of record representation pairs is prepared based at least in part on the language-agnostic embeddings. A machine learning model is trained using the record representations pairs to generate similarity scores for pairs of entity records whose text attributes are expressed in different languages.

Abstract: A plurality of resource requesters may be configured to consume a resource to perform a task. Each of the plurality of resource requesters can be allocated a resource budget to consume the resource to perform the task. An arbiter can select one of the plurality of resource requesters to consume the resource based on an arbitration scheme. When a resource requester is selected, the amount of resource consumed by the resource requester can be deducted from its resource budget. When the resource requester is idle for a number of cycles when selected, the corresponding resource budget can be further reduced to account for the actual amount of resource consumed and wasted by the resource requester, which can provide fairness in resource consumption over few rounds of arbitration.

Abstract: Described are systems, methods, and apparatus that detect keywords in one or more speech segments to authenticate that the speech is generated by the speaker as part of an intentional enrollment by the speaker into a service. For example, as a speech segment is received as part of an enrollment process, the speech segment may be converted into a log melspectrogram and the log melspectrogram may be processed using a machine learning model to determine if an expected keyword is represented by the log melspectrogram. If the keyword is detected, it may be determined that the speech output by the speaker is output as part of an intentional enrollment process.

Abstract: Systems and techniques are generally described for semantically segmenting videos. In various examples, a selection of a first video may be received. A first query to segment the first video into segments related to a first category of content may be received. A first plurality of segments related to the first category may be determined. In some examples, time code data representing the first plurality of segments may be sent to a remote computing device, wherein a video player of the remote computing device is effective to play the first plurality of segments based at least in part on the time code data.

Abstract: Techniques for identifying synchronization errors between audio and video are described herein. Audio portions in audio for media content may be identified based at least in part on a sound level associated with first respective segments of the audio portions. A subset of the audio portions may be selected based at least in part on a duration associated with the audio portions. For a segment of the subset a first number of frames in the audio and a second number of frames in the video for the segment may be determined. A determination may be made that the segment includes a conversation segment based at least in part on the first number of frames, the second number of frames, and a first threshold. A synchronization error may be identified in the conversation segment based on a difference between the audio and the video of the conversation segment.

Abstract: Data for training a machine learning algorithm to detect airborne objects is generated by capturing background images using a camera aboard an aerial vehicle, and generating a trajectory of a synthetic object, such another aerial vehicle, in three-dimensional space. The trajectory is projected into an image plane of the camera, determined from a pose of the camera calculated using inertial measurement unit data captured by the aerial vehicle. Images of the synthetic object may be rendered based on locations of the trajectory in the image plane at specific times. Pixel-accurate locations for the rendered images may be determined by calculating a homography from consecutive images captured using the camera, and adjusting locations of the trajectory using the homography. The rendered images may be blended into the images captured by the camera at such locations, and used to train a machine learning algorithm.