Quoting from the AMD official announcement:
AMD today announced that leading x86 operating system (OS) and virtual infrastructure (VI) vendors are embracing support for AMD’s native Quad-Core AMD Opteron processor, code-named “Barcelona.” Microsoft, Novell, Red Hat, Sun Microsystems and VMware are optimizing their operating systems, virtual infrastructures and supporting tools and middleware to take full advantage of the increased efficiencies, performance and decreased power consumption enabled by AMD quad-core technology.
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Microsoft Windows Server, SUSE Linux Enterprise Server from Novell, Red Hat Enterprise Linux, Sun Microsystems’ Solaris Operating System and VMware Infrastructure are expected to offer versions of their industry-leading operating systems and virtual infrastructures that work out-of-the-box with “Barcelona”, the industry’s first native x86 quad-core processors, providing improved performance across a range of applications. “Barcelona’s” enhancements, which will offer increased application performance within the same platform and power envelope as existing dual-core processors, include native quad-core capabilities, Enhanced AMD PowerNow! technology and Rapid Virtualization Indexing (formally “Nested Paging”), which is a new feature of AMD Virtualization technology.
VMware will support new AMD Rapid Virtualization Indexing since upcoming ESX Server 3.1, now in private beta.
Massimo Re Ferrè, Architect at IBM, posted a long and interesting comment on how this technology will impact virtualization. Read it here.