Embodiments enable recovery of push notification channels via session information associated with user identifiers. A proxy service creates session information describing push notification channels (e.g., subscriptions) for a user and associates the session information with a user identifier. The session information is stored in a cloud service or other storage area separate from the proxy service. After failure of a user computing device or the proxy service, the session information is obtained via the user identifiers and the push notification channels are re-created with the session information. In some embodiments, the proxy service enables delivery of the same notification to multiple computing devices associated with the user identifier.

Apparatus adapted for exascale computers are disclosed. The apparatus includes, but is not limited to at least one of: a system, data processor chip (DPC), Landing module (LM), chips including LM, anticipator chips, simultaneous multi-processor (SMP) cores, SMP channel (SMPC) cores, channels, bundles of channels, printed circuit boards (PCB) including bundles, floating point adders, accumulation managers, QUAD Link Anticipating Memory (QUADLAM), communication networks extended by coupling links of QUADLAM, log2 calculators, exp2 calculators, logALU, Non-Linear Accelerator (NLA), and stairways. Methods of algorithm and program development, verification and debugging are also disclosed. Collectively, embodiments of these elements disclose a class of supercomputers that obsolete Amdahl's Law, providing cabinets of petaflop performance and systems that may meet or exceed an exaflop of performance for Block LU Decomposition (Linpack).

Provided are a computer program product, system, and method for handling failure of a command to add a record to a log. The log has records at log addresses. Each record in the log includes a key and value and the log addresses map to physical addresses in the storage. A first command for a key and value pair for a record at a specified log address in the log to add to a selected log address in the log is sent. A second command for the key and value pair for the record at the specified log address with a resend parameter set is sent in response to not receiving the selected log address. In response to receiving the second command with the resend parameter set, the log is scanned to determine a log address having the key and value pair. The determined log address is returned.

Examples of techniques for transparent north port recovery of an error in an input/output device are disclosed. In one example implementation according to aspects of the present disclosure, a computer-implemented method may include: detecting, by a processing device, a command timeout; sending, by the processing device, an input/output (I/O) error signal to a host processing system connected to the hardware device via a north port of the hardware device; terminating, by the host processing system, a link between the north port of the hardware device and the host processing system; enabling, by the processing device, halt command forwarding on the hardware device; halting, by the processing device, commands upon detecting the halt command forwarding; and resetting, by the processing device, the link between the north port of the hardware device and the host processing system.

A conference system is provided with enhanced settings capabilities. A controller can poll for settings at each endpoint in a conference system and be able via the video stream to selectively display and compare settings among the endpoints. One location can push its settings to one or more locations to overcome failures or degradation in the conference. The settings between different controllers may be rationalized via a common denominator method or tabular method to build a knowledge of how to configure conferences and to automate responses to problems.

A method, computer program product, and computer system for performing, via a first computing device, a copy sweep operation to a first range of data on a source storage device. It may be determined that the copy sweep operation has failed. A message may be sent to a second computing device to suspend I/O operations to the first range of data. The copy sweep operation may be retried based upon, at least in part, determining that the copy sweep operation has failed, wherein the copy sweep operation may be retried without the first computing device receiving acknowledgement that the second computing device is suspending the I/O operations to the first range of data.

A system and method for using a dead letter queue to regulate host computing systems performing transformation or migration operations. The system and method including reading a message from a queue, the message including one or more references to a set of data objects, with the set of data objects including one or more data objects selected for a transformation operation according to a transformation scheme. The system and method further including performing a mitigation action upon determination that the message is one of a number of unsuccessfully processed messages in the queue that are associated with the computer system, when the number of unsuccessfully processed messages exceed a threshold.

According to an example, a retransmission sequence involving non-idempotent primitives in a fault-tolerant memory fabric may be modified. For example, a redundancy controller may request a sequence to access a stripe in the fault-tolerant memory fabric, wherein the sequence involves a non-idempotent primitive. In response to determining an expiration of a time threshold for the non-idempotent primitive, the redundancy controller may read other data in other cachelines in the stripe, calculate a new parity value by performing an idempotent exclusive-or primitive on the new data with the other data in the stripe, and write the new parity to the stripe using an idempotent write primitive.

Technology for determining an amount of time to wait to retry requests to a representational state transfer (REST) server system for a REST resource, where the time to wait is always chosen to be a prime number of time units (for example, slots, milliseconds). While currently conventional systems will sometimes use a prime number of time units to wait for a retry request, various embodiments of the present invention will always, and invariably, use a prime number of time units. The REST resource may be, for example, a REST application programming interface (API) that is requested by and delivered to a client system using hypertext transfer protocol (HTTP).

Provided are a computer program product, system, and method for providing track access reasons for track accesses resulting in the release of prefetched cache resources for the track. A first request for a track is received from a process for which prefetched cache resources to a cache are held for a second request for the track that is expected. A track access reason is provided for the first request specifying a reason for the first request. The prefetched cache resources are released before the second request to the track is received. Indication is made in an unexpected released track list of the track and the track access reason for the first request.