Abstract:
A system and method for maintaining ordering in completion and retransmit operations in an RDMA environment. A system is provided for handling a completion process in an remote data memory access (RDMA) environment having a RequestOut channel (16) and a ResponseOut channel (18), comprising: a descriptor list (12, 14) for each channel, wherein each descriptor list (12, 14) includes a message descriptor for each message in the channel; an update mechanism (25) for updating a message length field in the message descriptor with a sequence number of a last byte in the message whenever a channel swap occurs between the RequestOut channel (16) and the ResponseOut channel (18); an acknowledgement (Ack) completion system that examines values in a completion context (22) and compares a sequence number of a next to complete message with a last acknowledged sequence number to determine if the message should be completed; and a read request completion system that performs completion of a read request.
Abstract:
PROBLEM TO BE SOLVED: To provide a method to process the placement and distribution of aligned DDP segment by a method which is different from placement and distribution of non-aligned DDP segment. SOLUTION: A network interface controller performs direct data placement for a memory when all segments connected specifically are aligned, i.e., carries out the cut-through without accessing a reassembly buffer, and moves the data through the reassembly buffer when all segments are non-aligned. The validation of CRC is performed for a majority of inbound DDP segments, then, the TCP acknowledgement response to confirm segment receiving can be transmitted. In the method to calculate the CRC value, each TCP segment starts with an aligned DDP segment, and the first two bytes of TCP payload is supposed to be an MPA length field of an MPA frame. COPYRIGHT: (C)2011,JPO&INPIT
Abstract:
A method and system for completion coalescing by a Transmission Control Protocol (TCP) receiver (e.g., in a TCP/IP offload engine (TOE)). The method comprises: processing inbound TCP segments; and performing completion processing of the inbound TCP segments.
Abstract:
An RNIC implementation that performs direct data placement to memory where all segments of a particular connection are aligned, or moves data through reassembly buffers where all segments of a particular connection are non-aligned. The type of connection that cuts-through without accessing the reassembly buffers is referred to as a "Fast" connection because it is highly likely to be aligned, while the other type is referred to as a "Slow" connection. When a consumer establishes a connection, it specifies a connection type (S2). The connection type can change from Fast to Slow and back. The invention reduces memory bandwidth, latency, error recovery using TCP retransmit and provides for a "graceful recovery" from an empty receive queue. The implementation also may conduct CRC validation (S11, S6) for a majority of inbound DDP segments in the Fast connection before sending a TCP acknowledgement (Ack) confirming segment reception.
Abstract:
A network interface controller implementation (S152) that performs direct data placement to memory where all segments of a particular connection are aligned, i.e. cuts-through without accessing reassembly buffers (S159) (i.e., a "Fast" connection type), or if all segments are non-aligned moves data through reassembly buffer (S159) (i.e., "Slow" connection type). The type of connection can change from Fast to Slow and back. The implementation preferably conducts CRC validation (S154) for a majority of inbound DDP segments in the Fast connection before sending a TCP acknowledgement (S156) confirming segment reception. The method of computing a CRC value (S151) according to the present invention assumes that each TCP segment starts with an aligned DDP segment and that the first two bytes of a TCP payload is an MPA length field of an MPA frame.
Abstract:
An RNIC (16) implementation that performs direct data placement to memory where all segments of a particular connection are aligned, or moves data through reassembly buffers (34) where all segments of a particular connection are non-aligned. The type of connection that cuts-through without accessing the reassembly buffers (34) is referred to as a "Fast" connection because it is highly likely to be aligned, while the other type is referred to as a "Slow" connection. When a consumer establishes a connection, it specifies a connection type. The connection type can change from Fast to Slow and back. The invention reduces memory bandwidth, latency, error recovery using TCP retransmit and provides for a "graceful recovery" from an empty receive queue. The implementation also may conduct CRC validation for a majority of inbound DDP segments in the Fast connection before sending a TCP acknowledgement (Ack) confirming segment reception.