Abstract: A speed-enhancing drilling tool includes an upstream drill string (10), which has a drive motor and a first driving rod coupled therewith, a downstream drilling bit; and a percussive device connected between the upstream drilling string and the downstream drilling bit. The first driving rod extending axially and the drive motor are configured to drive the first driving rod in rotation. The percussive device has a rotary driving part having an upper end engaged with the first driving rod to rotate together therewith; and a rotary working part having an upper end engaged with a lower end of the rotary driving part and a lower end connected with the downstream drilling bit. The rotary working part can be driven by the rotary driving part to rotate about its axis, and axially movable relative thereto; and a percussion generating part arranged around the rotary working part.

Abstract: Methods are provided for mitigating hash correlation. In this regard, a hash correlation may be found between a first switch and a second switch in a network. In this network, a first egress port is to be selected among a first group of egress ports at the first switch for forwarding packets, and a second egress port is to be selected among a second group of egress ports at the second switch for forwarding packets, where the first group has a first group size and the second group has a second group size. Upon finding the hash correlation, a new second group size coprime to the first group size may be selected, and the second group of egress ports may be mapped to a mapped group having the new second group size. The second switch may be configured to route packets according to the mapped group.

Abstract: Methods are provided for mitigating hash correlation. In this regard, a hash correlation may be found between a first switch and a second switch in a network. In this network, a first egress port is to be selected among a first group of egress ports at the first switch for forwarding packets, and a second egress port is to be selected among a second group of egress ports at the second switch for forwarding packets, where the first group has a first group size and the second group has a second group size. Upon finding the hash correlation, a new second group size coprime to the first group size may be selected, and the second group of egress ports may be mapped to a mapped group having the new second group size. The second switch may be configured to route packets according to the mapped group.

Abstract: Methods are provided for mitigating hash correlation. In this regard, a hash correlation may be found between a first switch and a second switch in a network. In this network, a first egress port is to be selected among a first group of egress ports at the first switch for forwarding packets, and a second egress port is to be selected among a second group of egress ports at the second switch for forwarding packets, where the first group has a first group size and the second group has a second group size. Upon finding the hash correlation, a new second group size coprime to the first group size may be selected, and the second group of egress ports may be mapped to a mapped group having the new second group size. The second switch may be configured to route packets according to the mapped group.

Abstract: This disclosure provides systems, methods and apparatus for providing a network verification system (NVS) to analyze and detect anomalies and errors within a network. The NVS requests forwarding tables from each of the switches within the network being analyzed, and generates directed forwarding graphs for each subnet within the network. Certain graph properties of the directed forwarding graphs are analyzed to detect anomalies or errors in the subnets represented by the directed forwarding graphs. In some implementations, the NVS can execute the generation of the directed forwarding graphs in parallel. In some implementations, the NVS can be implemented on a MapReduce system.

Abstract: Aspects of the present disclosure relate to detecting and repairing permanently pauses on a flow controlled fabric. In one aspect, one or more computing devices, such as a switch or a centralized controller, may detect whether a port of a network device receives one or more pause messages. The pause messages may instruct the network device to pause data transmission. Further, the one or more computing devices may determine a period of time during which the port receives the one or more pause messages and identify the port as a permanently paused port based on the determined period of time. The one or more computing devices may then reconfigure the permanently paused port to stop complying with the one or more pause messages.