KVM lead developer thinks that MMU para-virtualization is dead

Today Avi Kivity, the KVM lead developer, published a pretty bold statement on his personal blog: para-virtualization is dead.

While he’s saving the I/O para-virtualization drivers (Qumranet, which supports KVM, just released its first para-virtualized network drivers), he also thinks that upcoming nested paging technologies from AMD (the Rapid Virtualization Indexing or RVI) and Intel (the Extended Page Tables or EPT) will provide such performance boost that modifying the guest OS kernel to make it virtualization-aware will become a useless practice.

KVM support for AMD RVI is expected along with Linux kernel 2.6.26, while the support for Intel EPT will not come earlier than 2009-2010, when the CPU vendor will release its next generation processor Nehalem.

The position of Kivity is interesting per se but becomes even more interesting when compared to the recent position of VMware, which is now fully endorsing para-virtualization.

Who knows what Citrix, which acquired the most active para-virtualization promoter XenSource, thinks about this theory.