AMD prints 'Pacifica' virtualisation spec

Claims best architecture to host multiple OSes

By Tony Smith • Get more from this author

Posted in Servers, 25th May 2005 10:12 GMT

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AMD has published its 'Pacifica' specification - its answer to Intel's Virtualisation Technology (VT), which is intended to allow a desktop or server to run multiple operating systems simultaneously.

Intel is expected to announce VT-enabled Pentium 4 processors soon, possibly even this week, well ahead of its schedule for getting the technology into servers.

AMD has said it will ship virtualisation-aware client and server processors in Q1 2006, in both single- and dual-core chips.

Both systems provide a hardware framework for virtualisation, but it looks like the technique will still require specialist software, such as VMware and Xensource, to be of use. Think of VT and Pacifica more as technologies to take some of the processing burden off VMware's shoulders rather than a full-scale virtualisation system in its own right. AMD calls it "silicon enhanced virtualisation", for example.

AMD's approach centres on establishing a 'Hypervisor' system which sits between the CPU's processing core(s) and 'guest' code, whether that be multiple operating systems, different instances of the same OS, or even a 'service guest' remote admin module. The Hypervisor keys the multiple virtual machines into the single physical system. Pacifica essentially adds new instructions, such as VMRUN, and a virtual machine data structure, to the x86 core.

The company touts its Direct Connect Architecture - its mix of HyperTransport and on-chip memory controller - as the most suitable infrastructure for virtualisation.

AMD and Intel both see virtualisation as an enterprise-oriented technology - VT is coming to the P4 first because it's a key component of Intel's Active Management Technology, a remote maintenance and management system for corporate computing - but they also forecast a role of home users, particular in boxes with multiple users, such as home servers.

AMD said the specification would be made available here. ®