Patent · US Active

Preventing messaging queue deadlocks in a DMA environment

US8631086B2 · kind B2 · utility

4Cited by
14References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 2008
Grant dateJan 14, 2014
Priority date
Expiry dateSep 3, 2031

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F15/17331
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Embodiments of the invention may be used to manage message queues in a parallel computing environment to prevent message queue deadlock. A direct memory access controller of a compute node may determine when a messaging queue is full. In response, the DMA may generate an interrupt. An interrupt handler may stop the DMA and swap all descriptors from the full messaging queue into a larger queue (or enlarge the original queue). The interrupt handler then restarts the DMA. Alternatively, the interrupt handler stops the DMA, allocates a memory block to hold queue data, and then moves descriptors from the full messaging queue into the allocated memory block. The interrupt handler then restarts the DMA. During a normal messaging advance cycle, a messaging manager attempts to inject the descriptors in the memory block into other messaging queues until the descriptors have all been processed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.