Infiniband work and completion queue management via head and tail circular buffers with indirect work queue entries
US6789143B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2001 |
| Grant date | Sep 7, 2004 |
| Priority date | — |
| Expiry date | May 31, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/546
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A distributed computing system having (host and I/O) end nodes, switches, routers, and links interconnecting these components is provided. The end nodes use send and receive queue pairs to transmit and receive messages. The end nodes use completion queues to inform the end user when a message has been completely sent or received and whether an error occurred during the message transmission or reception process. A mechanism implements these queue pairs and completion queues in hardware. A mechanism for controlling the transfer of work requests from the consumer to the CA hardware and work completions from the CA hardware to the consumer using head and tail pointers that reference circular buffers is also provided. The QPs and CQs do not contain Work Queue Entries and Completion Queue Entries respectively, but instead contain references to these entries. This allows them to be efficient and constant in size, while the Work Queue Entries and Completion Queue Entries themselves can vary in size, for example to include a variable number of data segments. Additionally, several mechanisms are provided to improve the overall efficiency of this process under different memory configurations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.