Page stream sorter for DRAM systems
US7376803B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 19, 2004 |
| Grant date | May 20, 2008 |
| Priority date | — |
| Expiry date | Aug 30, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/1626
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Circuits, methods, and apparatus for reordering memory access requests in a manner that reduces the number of page misses and thus increases effective memory bandwidth. An exemplary embodiment of the present invention uses an exposed FIFO structure. This FIFO is an n-stage bubble compressing FIFO that preserves the order of requests but allows bypassing to avoid page misses and their resulting delays. A specific embodiment exploits DRAM page locality by maintaining a set of history registers that track the last bank and row usage. Embodiments of the present invention may limit the number of times a request may be bypassed by incrementing an associated bypass counter each time the request is bypassed. Further, to avoid continuous page misses that may occur if requests alternate between two rows, a hold-off counter may be implemented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.