System and method for fast branching using a programmable branch table

Methods and systems consistent with the present invention provide a programmable table which allows software to define a plurality of branching functions, each of which maps a vector of condition codes to a branch offset. This technique allows for a flexible multi-way branching functionality, using a conditional branch outcome table that can be specified by a programmer. Any instruction can specify the evaluation of arbitrary conditional expressions to compute the values for the condition codes, and can choose a particular branching function. When the processor executes the instruction, the processor's arithmetic/logical functional units evaluate the conditional expressions and then the processor performs the branch operation, according to the specified branching function.

FLEXIBLE PIN ALLOCATION

A system includes a memory and a controller. The controller may include a group of pads and an allocation register. The controller is configured to receive input signals corresponding to the group and allocate each one of the pads to output one of the input signals based on a configuration of pins of the memory. The controller is also configured to redirect the input signals, within the controller, based on the allocation of the pads and output the input signals from the controller into the pads. 120-. (canceled)21. A method comprising: 'the memory controller including the first pad and one or more other pads;', 'sending, by a memory controller of a device, a first signal from a first pad of the memory controller to a first pin of a first memory device of the device,'} the first memory device being different from the second memory device,', 'the first signal being of a first type,', 'the second signal being of a second type, and', 'the first type being different from the second type., 'sending, by the memory controller, a second signal from the first pad to a second pin of a second memory device of the device,'}22. The method of claim 21 ,where the first type is a Row Address Strobe signal type, andwhere the second type is a Column Address Strobe signal type.23. The method of claim 21 , where the first pad of the memory controller physically connects to the first pin of the first memory device and to the second pin of the second memory device.24. The method of claim 21 , further comprising:sending a first chip select signal from the memory controller to the first memory device before sending the first signal to the first memory device, andsending a second chip select signal from the memory controller to the second memory device before sending the second signal to the second memory device.25. The method of claim 21 , further comprising:receiving, by the memory controller, information regarding the first pin of the first memory device, and 'the register ensuring that ...

Combined input and output queue for packet forwarding in network devices

An apparatus for switching network traffic includes an ingress packet forwarding engine and an egress packet forwarding engine. The ingress packet forwarding engine is configured to determine, in response to receiving a network packet, an egress packet forwarding engine for outputting the network packet and enqueue the network packet in a virtual output queue. The egress packet forwarding engine is configured to output, in response to a first scheduling event and to the ingress packet forwarding engine, information indicating the network packet in the virtual output queue and that the network packet is to be enqueued at an output queue for an output port of the egress packet forwarding engine. The ingress packet forwarding engine is further configured to dequeue, in response to receiving the information, the network packet from the virtual output queue and enqueue the network packet to the output queue.

System and method for efficient packet replication

Methods and systems consistent with the present invention provide efficient packet replication in a router in order to multicast a stream of data. Packets are replicated and processed in a multithreaded environment. Embodiments consistent with the present invention implement a two-stage process for packet replication. The first stage thread will recirculate the packet to multiple second-stage threads. These second-stage threads will then create one or more outgoing copies of the packet. In this way, the copies are handled by multiple threads running in parallel.

Systems and methods for improving packet scheduling accuracy

A packet scheduler is configured to perform quality of service (QoS) scheduling on a per-data unit basis. A downstream processing engine is operatively connected to the packet scheduler for receiving forwarded packets. A feedback path is operatively connected between the downstream processing engine and the packet scheduler for transmitting a net data unit change value reflecting a change in packet size between an output of the packet scheduler and an output of the downstream processing engine.

Determining rate differential weighted fair output queue scheduling for a network device

A network device may receive packets and may calculate, during a time interval, an arrival rate and a departure rate, of the packets, at one of multiple virtual output queues. The network device may calculate a current oversubscription factor based on the arrival rate and the departure rate, and may calculate a target oversubscription factor based on an average of previous oversubscription factors associated with the multiple virtual output queues. The network device may determine whether a difference exists between the target oversubscription factor and the current oversubscription factor and may calculate, when the difference exists, a scale factor based on the current oversubscription factor and the target oversubscription factor. The network device may calculate new scheduling weights based on prior scheduling weights and the scale factor, and may process packets received by the multiple virtual output queues based on the new scheduling weights.

Combined input and output queue for packet forwarding in network devices

An apparatus for switching network traffic includes an ingress packet forwarding engine and an egress packet forwarding engine. The ingress packet forwarding engine is configured to determine, in response to receiving a network packet, an egress packet forwarding engine for outputting the network packet and enqueue the network packet in a virtual output queue. The egress packet forwarding engine is configured to output, in response to a first scheduling event and to the ingress packet forwarding engine, information indicating the network packet in the virtual output queue and that the network packet is to be enqueued at an output queue for an output port of the egress packet forwarding engine. The ingress packet forwarding engine is further configured to dequeue, in response to receiving the information, the network packet from the virtual output queue and enqueue the network packet to the output queue.

Branching to target address by adding value selected from programmable offset table to base address specified in branch instruction

Methods and systems consistent with the present invention provide a programmable table which allows software to define a plurality of branching functions, each of which maps a vector of condition codes to a branch offset. This technique allows for a flexible multi-way branching functionality, using a conditional branch outcome table that can be specified by a programmer. Any instruction can specify the evaluation of arbitrary conditional expressions to compute the values for the condition codes, and can choose a particular branching function. When the processor executes the instruction, the processor's arithmetic/logical functional units evaluate the conditional expressions and then the processor performs the branch operation, according to the specified branching function.

Combined input and output queue for packet forwarding in network devices

An apparatus for switching network traffic includes an ingress packet forwarding engine and an egress packet forwarding engine. The ingress packet forwarding engine is configured to determine, in response to receiving a network packet, an egress packet forwarding engine for outputting the network packet and enqueue the network packet in a virtual output queue. The egress packet forwarding engine is configured to output, in response to a first scheduling event and to the ingress packet forwarding engine, information indicating the network packet in the virtual output queue and that the network packet is to be enqueued at an output queue for an output port of the egress packet forwarding engine. The ingress packet forwarding engine is further configured to dequeue, in response to receiving the information, the network packet from the virtual output queue and enqueue the network packet to the output queue.

System and method for fast branching using a programmable branch table

Methods and systems consistent with the present invention provide a programmable table which allows software to define a plurality of branching functions, each of which maps a vector of condition codes to a branch offset. This technique allows for a flexible multi-way branching functionality, using a conditional branch outcome table that can be specified by a programmer. Any instruction can specify the evaluation of arbitrary conditional expressions to compute the values for the condition codes, and can choose a particular branching function. When the processor executes the instruction, the processor's arithmetic/logical functional units evaluate the conditional expressions and then the processor performs the branch operation, according to the specified branching function.

System and method for fast branching using a programmable branch table

Methods and systems consistent with the present invention provide a programmable table which allows software to define a plurality of branching functions, each of which maps a vector of condition codes to a branch offset. This technique allows for a flexible multi-way branching functionality, using a conditional branch outcome table that can be specified by a programmer. Any instruction can specify the evaluation of arbitrary conditional expressions to compute the values for the condition codes, and can choose a particular branching function. When the processor executes the instruction, the processor's arithmetic/logical functional units evaluate the conditional expressions and then the processor performs the branch operation, according to the specified branching function.

System and method for fast branching using a programmable branch table

Maintaining data unit order in a network switching device

Data units received by a network device may be classified into traffic flow classes in which the determined traffic flow class for a data unit may be dynamically refined as the data unit is processed by the network device. A dispatch component of the network device may receive data units associated with traffic flow classes. Parallel processing engines of the network device may receive the data units from the dispatch component and may generate, for a least one of the data units, a plurality of dynamically refined indications of the traffic flow class to which the data unit belongs. Additionally, an ordering component of the network device may include a plurality of re-order queues, where the at least one data unit successively progresses through at least two of the re-order queues in an order defined by the plurality of dynamically refined indications of the traffic flow class.

Combined input and output queue for packet forwarding in network devices

An apparatus for switching network traffic includes an ingress packet forwarding engine and an egress packet forwarding engine. The ingress packet forwarding engine is configured to determine, in response to receiving a network packet, an egress packet forwarding engine for outputting the network packet and enqueue the network packet in a virtual output queue. The egress packet forwarding engine is configured to output, in response to a first scheduling event and to the ingress packet forwarding engine, information indicating the network packet in the virtual output queue and that the network packet is to be enqueued at an output queue for an output port of the egress packet forwarding engine. The ingress packet forwarding engine is further configured to dequeue, in response to receiving the information, the network packet from the virtual output queue and enqueue the network packet to the output queue.

Combined input and output queue for packet forwarding in network devices

Combined input and output queue for packet forwarding in network devices

An apparatus for switching network traffic includes an ingress packet forwarding engine and an egress packet forwarding engine. The ingress packet forwarding engine is configured to determine, in response to receiving a network packet, an egress packet forwarding engine for outputting the network packet and enqueue the network packet in a virtual output queue. The egress packet forwarding engine is configured to output, in response to a first scheduling event and to the ingress packet forwarding engine, information indicating the network packet in the virtual output queue and that the network packet is to be enqueued at an output queue for an output port of the egress packet forwarding engine. The ingress packet forwarding engine is further configured to dequeue, in response to receiving the information, the network packet from the virtual output queue and enqueue the network packet to the output queue.