Structure for dynamic livelock resolution with variable delay memory access queue
US8131980B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 2008 |
| Grant date | Mar 6, 2012 |
| Priority date | — |
| Expiry date | Apr 6, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0804
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A design structure for resolving the occurrence of livelock at the interface between the processor core and memory subsystem controller. Livelock is resolved by introducing a livelock detection mechanism (which includes livelock detection utility or logic) within the processor to detect a livelock condition and dynamically change the duration of the delay stage(s) in order to alter the “harmonic” fixed-cycle loop behavior. The livelock detection logic (LDL) counts the number of flushes a particular instruction takes or the number of times an instruction re-issues without completing. The LDL then compares that number to a preset threshold number. Based on the result of the comparison, the LDL triggers the implementation of one of two different livelock resolution processes. These processes include dynamically configuring the delay queue within the processor into one of two different configurations and changing the sequence and timing of handling memory access instructions, based on the specific configuration of the delay queue.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.