Patent · US Expired

Mechanism to control the allocation of an N-source shared buffer

US7213087B1 · kind B1 · utility

35Cited by
66References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 31, 2000
Grant dateMay 1, 2007
Priority date
Expiry dateMay 27, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L49/90
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for ensuring fair and efficient use of a shared memory buffer. A preferred embodiment comprises a shared memory buffer in a multi-processor computer system. Memory requests from a local processor are delivered to a local memory controller by a cache control unit and memory requests from other processors are delivered to the memory controller by an interprocessor router. The memory controller allocates the memory requests in a shared buffer using a credit-based allocation scheme. The cache control unit and the interprocessor router are each assigned a number of credits. Each must pay a credit to the memory controller when a request is allocated to the shared buffer. If the number of filled spaces in the shared buffer is below a threshold, the buffer immediately returns the credits to the source from which the credit and memory request arrived. If the number of filled spaces in the shared buffer is above a threshold, the buffer holds the credits and returns the credits in a round-robin manner only when a space in the shared buffer becomes free. The number of credits assigned to each source is sufficient to enable each source to deliver an uninterrupted burst of…

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