Abstract: A method for synchronizing multicast message subflows in a switched network includes associating, with a processing device, a first destination identifier corresponding to a multicast message with a first queue that corresponds to a first output port of a switching device, associating, with a processing device, a second destination identifier corresponding to the multicast message with a second queue that corresponds to a second output port of the switching device, pausing the first queue in response to a message counter corresponding to the first queue crossing a first predetermined threshold, and unpausing the first queue in response to the message counter crossing a second predetermined threshold, wherein the message counter indicates a quantity of data that has been forwarded by the first queue but remains to be forwarded by the second queue.

Abstract: In one embodiment, a method includes selecting a flow from a head of a first control queue or a second control queue. The method also includes providing service to the selected flow. Moreover, the method includes decreasing a service credit of the selected flow by an amount corresponding to an amount of service provided to the selected flow. In another embodiment, a computer program product includes a computer readable storage medium having program code embodied therewith. The embodied program code is readable/executable by a device to select, by the device, a flow from a head of a first control queue or a second control queue. The embodied program code is also readable/executable to provide, by the device, service to the selected flow, and decrease, by the device, a service credit of the selected flow by an amount corresponding to an amount of service provided to the selected flow.

Abstract: A network fabric may divide a physical connection into a plurality of VLANs as defined by IEEE 802.1Q. Moreover, many network fabrics use Priority Flow Control to identify and segregate network traffic based on different traffic classes or priorities. Current routing protocols define only eight traffic classes. In contrast, a network fabric may contain thousands of unique VLANs. When network congestion occurs, network devices (e.g., switches, bridges, routers, servers, etc.) can negotiate to pause the network traffic associated with one of the different traffic classes. Pausing the data packets associated with a single traffic class may also stop the data packets associated with thousands of VLANs. The embodiments disclosed herein permit a network fabric to individually pause VLANs rather than entire traffic classes.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being adapted to: receive a plurality of flows, each flow comprising packets of data, assign a service credit to each of the plurality of flows, assign a weight parameter to each of the plurality of flows, select a flow from a head of a first control queue unless the first control queue is empty or there is indication that the first control queue should be avoided, wherein a flow is selected from a head of a second control queue when the first control queue is empty or there is indication that the first control queue should be avoided, provide a number of units of service to the selected flow, and decrease the selected flow's service credit by an amount corresponding to the number of units of service provided thereto.

Abstract: A system for hierarchical occupancy based congestion management includes a buffer embodied in a computer readable storage medium including a plurality of buffer units for storing packets of a data flow received from sources. The system includes a buffer manager that stores information about the packets stored in the buffer, including a selection criterion associated with each of the plurality of sources and a congestion estimator that monitors a congestion level in the buffer. The system also includes a occupancy sampler that randomly selects at least two occupied buffer units from the plurality of buffer units and identifies the source of the packet stored in each of the occupied buffer units and a congestion notification message generator that generates a congestion notification message; wherein if the congestion level in the buffer exceeds a threshold value the congestion notification message is sent to the identified source with a higher selection criteria.

Abstract: A method for hierarchical occupancy based congestion management includes receiving, by a computing device, a plurality of data flows, each of the plurality of data flows is received from a source and includes a plurality of data packets and storing the plurality of data packets in a buffer including multiple storage units. The method includes determining if the buffer is congested, responsive to determining the buffer is congested randomly selecting at least two occupied units of the buffer and identifying a source of each of the data packets stored in the occupied units of the buffer and generating a congestion notification message. The method also includes comparing a selection criterion associated with each identified source to determine which identified source has a higher selection criterion and sending the congestion notification message to the identified source with the higher selection criterion.

Abstract: A method for synchronizing multicast message subflows in a switched network includes associating, with a processing device, a first destination identifier corresponding to a multicast message with a first queue that corresponds to a first output port of a switching device, associating, with a processing device, a second destination identifier corresponding to the multicast message with a second queue that corresponds to a second output port of the switching device, pausing the first queue in response to a message counter corresponding to the first queue crossing a first predetermined threshold, and unpausing the first queue in response to the message counter crossing a second predetermined threshold, wherein the message counter indicates a quantity of data that has been forwarded by the first queue but remains to be forwarded by the second queue.

Abstract: A method for hybrid arrival-occupancy based congestion management includes increasing a recent arrivals counter associated with a data flow from one or more sources in response to receiving a data packet from one of the sources and storing the data packet in a buffer including multiple storage units. The method includes determining if a buffer is congested, randomly selecting an occupied unit of the buffer and determining the source of the packet stored in the occupied unit of the buffer, generating a congestion notification message, sending the congestion notification message to the source of the packet stored in the occupied unit of the buffer if the recent arrivals counter exceeds a threshold value and decreasing the recent arrivals counter associated with the source of the packet stored in the occupied unit of the buffer and discarding the congestion notification message if the recent arrivals counter has a zero value.

Abstract: A system to improve a Converged Enhanced Ethernet network may include a controller having a computer processor connected to a layer 2 endpoint buffer. The system may also include a manager executing on the controller to monitor the layer 2 endpoint buffer by determining buffer data packet occupancy and/or rate of change in the buffer data packet occupancy. The system may further include a reporter to notify a congestion source of the layer 2 endpoint buffer based upon the buffer data packet occupancy and/or rate of change in the buffer data packet occupancy.

Abstract: A system to improve a Converged Enhanced Ethernet network may include a controller having a computer processor connected to a layer 2 endpoint buffer. The system may also include a manager executing on the controller to monitor the layer 2 endpoint buffer by determining buffer data packet occupancy and/or rate of change in the buffer data packet occupancy. The system may further include a reporter to notify a congestion source of the layer 2 endpoint buffer based upon the buffer data packet occupancy and/or rate of change in the buffer data packet occupancy.

Abstract: A method for buffer occupancy based congestion management includes receiving, by a computing device, a data stream including a plurality of packets from a plurality of sources and storing the packets in a buffer that includes multiple storage units. The method also includes determining if the buffer is congested, responsive to determining that the buffer is congested randomly selecting an occupied unit of the buffer and determining the source of the packet stored in the occupied unit of the buffer and sending a congestion notification message to the source of the packet stored in the occupied unit of the buffer.

Abstract: A method and circuit for implementing a network manager quarantine mode in an interconnect system, and a design structure on which the subject circuit resides are provided. A respective network manager on a source interconnect chip and a destination interconnect chip sends end-to-end (ETE) heartbeats on each path between the source and destination interconnect chips. Each network manager maintains a heartbeat table with counters to track each path to each destination interconnect chip. When a first network manager of a first interconnect chip detects a change from at least one valid path to no working paths for a second interconnect chip of the interconnect chips, the quarantine mode is established for a programmable quarantine time interval and all paths are prevented from advertising good heartbeats during the quarantine time interval.

Abstract: The distributed switch may include a plurality of chips (i.e., sub-switches) on a switch module. These sub-switches may receive from a computing device connected to a Tx/Rx port a multicast data frame (e.g., an Ethernet frame) that designates a plurality of different destinations. Instead of simply using one egress connection interface to forward the copies of the data frame to each of the destinations sequentially, the sub-switch may use a plurality of a connection interfaces to transfer copies of the multicast data frame simultaneously. The port that receives the multicast data frame can borrow the connection interfaces (and associated hardware such as buffers) assigned to these other ports to transmit copies of the multicast data frame simultaneously.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being adapted to: receive a plurality of flows, each flow comprising packets of data, assign a service credit to each of the plurality of flows, assign a weight parameter to each of the plurality of flows, select a flow from a head of a first control queue unless the first control queue is empty or there is indication that the first control queue should be avoided, wherein a flow is selected from a head of a second control queue when the first control queue is empty or there is indication that the first control queue should be avoided, provide a number of units of service to the selected flow, and decrease the selected flow's service credit by an amount corresponding to the number of units of service provided thereto.

Abstract: A method and circuit for implementing end-to-end credit management for enhanced large packet reassembly in an interconnect system, and a design structure on which the subject circuit resides are provided. A transport layer provides buffering and credit control for a super packet received from a source device. A source transport layer sends an End-to-End (ETE) credit request message to a destination transport layer for an outstanding super packet transmission to a destination device. The destination transport layer grants credit to allow at least one source to send a super packet to the destination. The source transport layer fragments the super packet into multiple packets and sends all packets of the super packet only responsive to the credit request being granted by the destination transport layer that is needed to send all packets of the super packet.

Abstract: A method for deadlock resolution in end-to-end credit protocol includes receiving a data frame and determining a number of credits required to transmit the data frame. The method also includes requesting and receiving credits from an end controller and responsively incrementing a credit counter. The method further includes determining if a value of the credit counter is greater than the number of credits required to transmit the data frame. Based on determining that the value of the credit counter is at least the number of credits required, the method includes transmitting the data frame to the end controller and decreasing the value of the credit counter by the number of credits required to transmit the data frame. Based on determining that the value of the credit counter is less than the number of credits required, the method includes transmitting a credit shortage notification to the end controller.

Abstract: A system for deadlock resolution in end-to-end credit protocol includes a plurality of source controllers configured to receive data frames on an incoming link, wherein each source controller includes a plurality of credit counters. The system also includes a plurality of end controllers configured to receive data frames from the plurality of source controllers, wherein each end controller includes a buffer credit counter, a plurality of request counters, and an output buffer. Each of the plurality of credit counters corresponds to one of the plurality of end controllers and stores a number of credits received from that end controller. The buffer credit counter of each end controller stores a number of available credits of the end controllers. Each of the request counters corresponds to one of the plurality of source controllers and stores a number of credit requests received from that source controller.

Abstract: Systems and methods to multicast data frames are provided. A particular apparatus includes a plurality of computing nodes and a distributed virtual bridge. The distributed virtual bridge includes a plurality of bridge elements coupled to the plurality of computing nodes. The plurality of bridge elements are configured to forward a copy of a multicast data frame to the plurality of computing nodes using group member information associated with addresses of the plurality of server computers. A controlling bridge coupled to the plurality of bridge elements is configured to communicate the group member information to the plurality of bridge elements.

Abstract: A method for deadlock resolution in end-to-end credit protocol includes receiving a data frame and determining a number of credits required to transmit the data frame. The method also includes requesting and receiving credits from an end controller and responsively incrementing a credit counter. The method further includes determining if a value of the credit counter is greater than the number of credits required to transmit the data frame. Based on determining that the value of the credit counter is at least the number of credits required, the method includes transmitting the data frame to the end controller and decreasing the value of the credit counter by the number of credits required to transmit the data frame. Based on determining that the value of the credit counter is less than the number of credits required, the method includes transmitting a credit shortage notification to the end controller.

Abstract: A system for deadlock resolution in end-to-end credit protocol includes a plurality of source controllers configured to receive data frames on an incoming link, wherein each source controller includes a plurality of credit counters. The system also includes a plurality of end controllers configured to receive data frames from the plurality of source controllers, wherein each end controller includes a buffer credit counter, a plurality of request counters, and an output buffer. Each of the plurality of credit counters corresponds to one of the plurality of end controllers and stores a number of credits received from that end controller. The buffer credit counter of each end controller stores a number of available credits of the end controllers. Each of the request counters corresponds to one of the plurality of source controllers and stores a number of credit requests received from that source controller.