Abstract: A system, methods and apparatus perform remote access commands between nodes and allow preemption of context resources in an architecture such as Infiniband. The system detects an original request in a request queue for a data access task to access data from a first node to a second node and issues a first request from a first node to a second node. The first request requests the data access task be performed between the first node and the second node. The system receives, at the first node, a first response from the second node that partially completes the data access task. The system issues at least one subsidiary request from the first node to the second node to further complete the data access task between the first node and the second node. The subsidiary request(s) are based on an amount of partial completion of the data access task between the first node and the second node.

Abstract: A plurality of PCIe switch complexes are interposed between a plurality of I/O devices and a plurality of microprocessor complexes. Each PCIe switching complex comprises a plurality of PCIe switches wherein each switch possesses at least one non-transparent port. The non-transparent port is used to cross-couple each PCIe switch creating an active matrix of paths between the HBAs associated with each I/O device and each microprocessor. The paths between each HBA (I/O device) and each microprocessor are mapped using a recursive algorithm providing each I/O device with direct memory access to each microprocessor.

Abstract: Data buffering allocation in a microprocessor complex for a request of memory allocation is supported through a remote buffer batch allocation protocol. The separation of control and data placement allows simultaneous maximization of microprocessor complex load sharing, and minimization of inter-processor signaling/metadata migration. Separating processing control from data placement allows the location of data buffering to be chosen so as to maximize bus bandwidth utilization and achieve non-blocking switch behavior. This separation reduces the need for inter-processor communication and associated interrupts thus improving computation efficiency and performance.

Abstract: A plurality of PCIe switch complexes are interposed between a plurality of I/O devices and a plurality of microprocessor complexes. Each PCIe switching complex comprises a plurality of PCIe switches wherein each switch possesses at least one non-transparent port. The non-transparent port is used to cross-couple each PCIe switch creating an active matrix of paths between the HBAs associated with each I/O device and each microprocessor. The paths between each HBA (I/O device) and each microprocessor are mapped using a recursive algorithm providing each I/O device with direct memory access to each microprocessor.

Abstract: Dual ported Input/Output (“I/O”) routers couple I/O devices to a cross-coupled switching fabric providing multiple levels of data path redundancy. Each I/O router possesses two or more internal ports allowing each I/O router to access multiple switches in a cross-coupled switching fabric. The additional redundant paths between each I/O device and each microprocessor complex provide additional means to balance data traffic and thereby maximize bandwidth utilization. I/O routers can be interleaved with single HBAs establishing access a switching fabric that uses cross-coupled nontransparent ports thus providing each I/O device with multiple paths upon which to pass data. Data paths are identified by a recursive address scheme that uniquely identifies each data path option available to each I/O device.

Abstract: Data buffering allocation in a microprocessor complex for a request of memory allocation is supported through a remote buffer batch allocation protocol. The separation of control and data placement allows simultaneous maximization of microprocessor complex load sharing, and minimization of inter-processor signaling/metadata migration. Separating processing control from data placement allows the location of data buffering to be chosen so as to maximize bus bandwidth utilization and achieve non-blocking switch behavior. This separation reduces the need for inter-processor communication and associated interrupts thus improving computation efficiency and performance.

Abstract: Methods and apparatus are disclosed for enabling nodes in a data network having interconnect links to continue to transmit data when a link fails. This is done in realtime, in a manner transparent to upper-level clients, and at a hardware level without software intervention. A method is described in which a data packet is received or stored in a transmitter buffer at an originating node having a failed link where the data packet is scheduled to use the failed link. The data packet is routed to a failover storage area. The failover storage area is a shared resource in the node and consists of two first-in, first-out stacks for processing and routing the failover data packets. If needed, an alternative link is selected for the data packet and the data packet is routed to a transmitter associated with the alternative link. An alternative link is selected using a primary and secondary routing table, also part of the shared resource of the node.

Abstract: An optical transmitter for transmitting a first output data signal and a second output data signal, the optical transmitter comprising: a phase-locked-loop, the phase-locked-loop operable to receive a reference clock signal; a clock-recovery circuit, the clock-recovery circuit coupled to the phase-locked-loop, the clock-recovery circuit operable to receive a first input data signal; a latch-decision circuit, the latch-decision circuit coupled to the clock-recovery circuit; a latch, the latch coupled to the latch-decision circuit, the latch operable to receive the first input data signal and the second input data signal; a first electro-optical converter, the first electro-optical converter coupled to the latch, the first electro-optical converter operable to transmit the first output data signal; and a second electro-optical converter, the second electro-optical converter coupled to the latch, the second electro-optical converter operable to transmit the second output data signal.

Abstract: Methods and components in an interconnect system for improving the performance of the system with respect to increasing bandwidth in a serial link, increasing the processing speed of a packet in a node, and improving the calibration of links in the system are described. In one aspect of the present invention, a method of encoding framing data in a packet such that less than the normal number of framing bits is required. For example, a flit, the data unit sent over a serial link in one clock cycle, can be 88 bits in length, and a packet can be made up of one, two, or four flits. If the packet is a one- flit packet, two framing bits are inserted into the packet. If the packet is two flits, four framing bits are inserted into the packet, and if it is a four-flit packet, eight framing bits are inserted.

Abstract: A system and method for superimposing a sequence number of a packet into the CRC segment of the packet thereby allowing more bandwidth in the payload portion of the packet for carrying data is described. Also described is a method of acquiring additional information on the type of error in a packet, e.g., data transmission errors or sequence errors, from analyzing a CRC error. For example, a reported CRC error can be the result of the receipt of a packet with a sequence number the receiver is not expecting (which is a normal occurrence on transmission links due to transmitters resending packets that a receiver has already accepted) or can result from a real error in the transmission of a packet. A first error code check (CRC) value is calculated for the payload segment of a data packet. A second CRC value is calculated for the sequence number of the data packet. The first CRC value and the second CRC value are combined thereby creating a third CRC value.

Abstract: A method and device for virtual memory support in a computer system using a mapping structure for address translation. Mapping indicators are associated with each process context and each mapping structure entry. When a context is demapped the mapping indicator associated with the context is changed and the mapping indicator in each mapping structure entry is employed to immediately invalidate further memory accesses for that context.

Abstract: A central node in a network computes for, and sends to, each node a forwarding table which consists of the set of neighbors to which the node should forward a message intended for a particular destination. The message includes a version number in the packet field header indicating which forwarding table version the node should use to forward the packet. The node does not begin marking and forwarding packets according to the new version number immediately. The node may wait a period of time after receiving the new table or may wait until receiving notification from the fabric manager to begin using the new version number. When a node receives a message from an end node, it inserts either the most recently received version number in one embodiment or uses the version dictated by the fabric manager in another embodiment.

Abstract: System and method for rapidly calculating CRC values for messages including encoded bits is described. Tabularized CRC values are used in combination with a logical grid to quickly determine an appropriate CRC value of a message. This determination can take into account encoded inversion bits in the message. A collection of pre-calculated CRC values are arranged in a single-column table and then implemented with selected bits of a message by superimposing the bits in each CRC value onto a logical grid. Vertical lines of the grid are associated with 30 exclusive OR (XOR) gates and horizontal lines are associated with bits in an 88-bit message (or the 30 bits of a CRC value or with 8 bits of a sequence number). Through this grid, the inputs to the XOR gates are determined, thereby facilitating rapid calculations of CRC values due to the high processing speeds possible in XOR gates.

Abstract: A method and device for virtual memory support in a computer system using a mapping structure for address translation. Mapping indicators are associated with each process context and each mapping structure entry. When a context is demapped the mapping indicator associated with the context is changed and the mapping indicator in each mapping structure entry is employed to immediately invalidate further memory accesses for that context.

Abstract: An optical receiver for receiving a first input data signal and a second input data signal, the optical receiver comprising: a first photo-detector, the first photo-detector operable to receive the first input data signal and operable to output a first electrical signal; a second photo-detector, the second photo-detector operable to receive the second input data signal and operable to output a second electrical signal; a phase-locked-loop, the phase-locked-loop operable to receive a reference clock signal; a clock-recovery circuit, the clock-recovery circuit coupled to the phase-locked-loop, the clock-recovery circuit operable to receive the first electrical signal; a latch-decision circuit, the latch-decision circuit coupled to the clock-recovery circuit; and a latch, the latch coupled to the latch-decision circuit, the latch operable to receive the first electrical signal and the second electrical signal.

Abstract: An optical transmitter for transmitting a first output data signal and a second output data signal, the optical transmitter comprising: a phase-locked-loop, the phase-locked-loop operable to receive a reference clock signal; a clock-recovery circuit, the clock-recovery circuit coupled to the phase-locked-loop, the clock-recovery circuit operable to receive a first input data signal; a latch-decision circuit, the latch-decision circuit coupled to the clock-recovery circuit; a latch, the latch coupled to the latch-decision circuit, the latch operable to receive the first input data signal and the second input data signal; a first electro-optical converter, the first electro-optical converter coupled to the latch, the first electro-optical converter operable to transmit the first output data signal; and a second electro-optical converter, the second electro-optical converter coupled to the latch, the second electro-optical converter operable to transmit the second output data signal.

Abstract: A massively-parallel computer includes a plurality of processing nodes and at least one control node interconnected by a network. The network faciliates the transfer of data among the processing nodes and of commands from the control node to the processing nodes. Each processing node includes an interface for transmitting data over, and receiving data and commands from, the network, at least one memory module for storing data, a node processor and an auxiliary processor. The node processor receives commands received by the interface and processes data in response thereto, in the process generating memory access requests for facilitating the retrieval of data from or storage of data in the memory module. The node processor further controlling the transfer of data over the network by the interface. The auxiliary processor is connected to the memory module and the node processor.

Abstract: An information transfer system includes a transmitter and a receiver for transferring information over a differential communication link. The transmitter circuit includes a plurality of gated driver circuits each associated with one of a plurality separate phases of a clock signal, all of the gated driver circuits having respective outputs connected to a differential driver. Each gated driver circuit receives at a respective input a respective one of a plurality of selected information signals and transmits it over the communication link in response to the associated clock signal phase.

Abstract: A massively-parallel computer includes a plurality of processing nodes and at least one control node interconnected by a network. The network faciliates the transfer of data among the processing nodes and of commands from the control node to the processing nodes. Each each processing node includes an interface for transmitting data over, and receiving data and commands from, the network, at least one memory module for storing data, a node processor and an auxiliary processor. The node processor receives commands received by the interface and processes data in response thereto, in the process generating memory access requests for facilitating the retrieval of data from or storage of data in the memory module. The node processor further controlling the transfer of data over the network by the interface. The auxiliary processor is connected to the memory module and the node processor.

Abstract: An information transfer system transfers information, in the form of at least one digital data word, from an source operating in a first clock signal domain defined by a first clock signal, to a destination operating in a second clock signal domain defined by a second clock signal. The information transfer system includes a buffer, a buffer storage element, a buffer retrieval element and a synchronizer. The buffer storage element stores the data word in the buffer under control of a data word present indication, and the buffer retrieval element retrieves the data word from the buffer under control of the second clock signal and a synchronized data word present indication. The synchronizer generates the synchronized data word present indication in response to the first clock signal, the second clock signal, and the data word present indication, thereby to synchronize the data word present indication from the first clock signal domain into the second clock signal domain.