KVM on Track for World Domination

Red Hat Senior Engineer Chris Wright recently spoke about Red Hat Enterprise Linux, the Linux ecosystem, and the Kernel-based Virtual Machine (KVM) at the LinuxCon conference.  He jokingly told the audience that, "[The KVM project is] on track for total world domination."  Red Hat uses the VM for its RHEL distribution ever since it purchased Qumranet in 2008 and abandoned Xen.  Today, KVM has high-profile contributors like IBM, Intel, and Novell.

Red Hat sees the trajectory of businesses that are migrating their workloads to the cloud.  The open source company believes that KVM will have a major opportunity to flourish and gain ubiquity in the cloud.  KVM's strength comes from the fact that it is simply a kernel module that runs virtual machines on top of Linux, which has a well-supported ecosystem.  

KVM has come a long way since its more limited versions that couldn't provide as many virtual CPUs.  Today KVM can scale up to 64 virtual CPUs.  KVM developers have also been working on improving threading, pooling, and overall I/O performance as a result.  However, KVM already has formidable performance specs, achieving 85% of bare-metal performance for virtual guest operating systems.  Adding the high-performance I/O has not added any CPU overhead.  Essentially, Wright says they're increasing throughput while improving CPU efficiency.

Contributions from Cisco and a technology called Vhost are also adding to the list of things that KVM can do.  Vhost enables lower network latency by requiring less resources.  Cisco has integrated their VN-Link technology to make the networking infrastructure more aware of virtual machines.  Finally, KVM is on its way to supporting "transparent huge pages".  These enable multi-megabyte memory pages that can be allocated dynamically from 4kB memory blocks.  The transparent huge pages will essentially improve the performance of VMs with memory-intensive workloads.