Example implementations relate to consensus protocols in a stretched network. According to an example, a distributed system includes continuously monitoring network performance and/or network latency among a cluster of a plurality of nodes in a distributed computer system. Leadership priority for each node is set based at least in part on the monitored network performance or network latency. Each node has a vote weight based at least in part on the leadership priority of the node. Each node's vote is biased by the node's vote weight. The node having a number of biased votes higher than a maximum possible number of votes biased by respective vote weights received by any other node in the cluster is selected as a leader node.

A method and apparatus is disclosed herein for use of a connectivity manager and a network infrastructure including the same. In one embodiment, the network infrastructure comprises one or more physical devices communicably coupled into a physical network infrastructure or via the overlay provided by the physical servers; and a virtual network domain containing a virtual network infrastructure executing on the physical network infrastructure. In one embodiment, the virtual network domain comprises one or more virtual network functions connected together through one or more links and executing on the one or more physical devices, and one or more interfaces coupled to one or more network functions via one or more links to communicate data between the virtual network domain and at least one of the one or more physical devices of the physical network infrastructure while the virtual network domain is isolated from other virtual infrastructures executing on the physical network infrastructure.

A memory system includes a processing device (e.g., a controller implemented using a CPU, FPGA, and/or logic circuitry) and memory regions (e.g., in a flash memory or other non-volatile memory) storing data. The processing device receives an access request from a host system that is requesting to read the stored data. In one approach, the memory system is configured to: receive, from the host system over a bus, a read command to access data associated with an address in a non-volatile memory; in response to receiving the read command, access, by the processing device, multiple copies of data stored in at least one memory region of the non-volatile memory; match, by the processing device, data from the copies with each other; select, based on matching data from the copies with each other, first data from a first copy of the copies; and provide, to the host system over the bus, the first data as output data.

Techniques are disclosed relating to methods that include initializing, by a computer in a computer system, an event counter that includes a plurality of sub-counter groups, each plurality of sub-counter groups including at least two sub-counters located on different nodes of a plurality of nodes in the computer system. In response to an occurrence of an event associated with the event counter, the method may include the computer selecting a particular sub-counter group of the plurality of sub-counter groups to update, and sending, to sub-counters corresponding to the particular sub-counter group, a request to update a sub-counter value for the particular sub-counter group. In response to a request for a current count value of the event counter, the method may include outputting, by the computer, a sum of the sub-counter values for the plurality of sub-counter groups as the current count value.

Systems and techniques are provided for Byzantine agreement in open networks. An indication to change a validation network for an open network from a current validation network to a next validation network may be broadcast. An agreement to change to the validation network to the next validation network may be. An instance of external validity multi-valued Byzantine agreement may be run to determine a continuing sequence number to be used by the next validation network based on the sequence numbers of amendments applied to decentralized database copies stored node computing devices of the open network. The next validation network may be switched to as the validation network for the open network after the continuing sequence number is determined. An amendment validated by the next validation network may be applied to a decentralized database copy. The amendment may include a sequence number that is higher than the continuing sequence number.

A parallel processing system includes at least three processors operating in parallel, state monitoring circuitry, and state reload circuitry. The state monitoring circuitry couples to the at least three parallel processors and is configured to monitor runtime states of the at least three parallel processors and identify a first processor of the at least three parallel processors having at least one runtime state error. The state reload circuitry couples to the at least three parallel processors and is configured to select a second processor of the at least three parallel processors for state reload, access a runtime state of the second processor, and load the runtime state of the second processor into the first processor. Monitoring and reload may be performed only on sub-systems of the at least three parallel processors. During reload, clocks and supply voltages of the processors may be altered. The state reload may relate to sub-systems.

The method includes creating and sending a change request for a change to the system configuration of the hardware system by means of a first hardware component of the plurality of hardware components, receiving the change request by means of the further hardware components of the plurality of hardware components, checking the change request by means of the further hardware components for compatibility of the change request with the configuration of the particular receiving hardware component by using configuration data of the receiving hardware component, in the case that the requested change to the system configuration is compatible with the configuration of the receiving hardware component, generating and sending an approval of the change to the system configuration by means of the receiving hardware component, and in the case that an approval quorum of the hardware components that is necessary for consent is achieved, entering the requested change to the system configuration of the hardware system into the block chain, implementing the requested change to the system configuration in the hardware system.

Techniques are provided for metadata management for enabling automated switchover. An initial quorum vote may be performed before a node executes an operation associated with metadata comprising operational information and switchover information. After the initial quorum vote is performed, the node executes the operation upon one or more mailbox storage devices. Once the operation has executed, a final quorum vote is performed. The final quorum vote and the initial quorum vote are compared to determine whether the operation is to be designated as successful or failed, and whether any additional actions are to be performed.

An information processing device and information processing method with improved error tolerance are implemented. There is included a data processing unit that executes lockstep processing in which a plurality of processing systems executes the same task and error verification is performed by comparing execution results. In a case where an error is detected in the lockstep processing, the data processing unit increases supply voltage to a CPU circuit system that executes the task, processing of lowering a supply clock, or the like, as control for improving noise tolerance of the CPU circuit system, and moreover, performs re-execution processing of the task by using more processing systems than the processing systems before the error detection.

A parallel processing system includes at least three parallel processors, state monitoring circuitry, and state reload circuitry. The state monitoring circuitry couples to the at least three parallel processors and is configured to monitor runtime states of the at least three parallel processors and identify a first processor of the at least three parallel processors having at least one runtime state error. The state reload circuitry couples to the at least three parallel processors and is configured to select a second processor of the at least three parallel processors for state reload, access a runtime state of the second processor, and load the runtime state of the second processor into the first processor. Monitoring and reload may be performed only on sub-systems of the at least three parallel processors. During reload, clocks and supply voltages of the processors may be altered. The state reload may relate to sub-systems.