Virtualization system for computers that use address space indentifiers
US7409487B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2003 |
| Grant date | Aug 5, 2008 |
| Priority date | — |
| Expiry date | Jan 20, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2009/45583
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A virtual computer system including multiple virtual machines (VMs) is implemented in a physical computer system that uses address space identifiers (ASIDs). Each VM includes a virtual translation look-aside buffer (TLB), in which guest software, executing on the VM, may insert address translations, with each translation including an ASID. For each ASID used by guest software, a virtual machine monitor (VMM), or other software unit, assigns a unique shadow ASID for use in corresponding address translations in a hardware TLB. If a unique shadow ASID is not available for a newly used guest ASID, the VMM reassigns a shadow ASID from a prior guest ASID to the new guest ASID, purging any entries in the hardware TLB corresponding to the prior guest ASID. Assigning unique shadow ASIDs limits the need for TLB purges upon switching between the multiple VMs, reducing the number of TLB miss faults, and consequently improving overall processing efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.