Virtualization is all about sharing resources of IT systems to get better usage out of them — to lower costs and to make it a more productive environment, with a better return on investment. Of course, you need a sufficiently large server with enough power and capacity so it is worth sharing the resources between different workloads. But once you have decided to virtualize, a key issue to consider is how the source code for the virtualization hypervisor is developed. That brings us to the importance of open source hypervisors, and in particular, KVM (the Kernel-based Virtual Machine).
KVM stands out from other virtualization technologies because it is based on Linux, and therefore benefits from the thousands of programmers in the open source community that has contributed to Linux. A key aspect of KVM and its development communities is that there is one code stream that all developers are focused on, so that it does not become splintered as happened to Xen, an earlier open source virtualization project.
KVM offers a high level of scalability, and this has to do with the fact that it is building on the scalability already inside Linux, with the result that it can support large memory, and many processor cores. In fact, the top seven SPECvirt benchmarks, which are the industry standard in terms of virtualization benchmarks, all use KVM — whether they have been done on IBM or on HP hardware. Recently, Red Hat Enterprise Virtualization on IBM System x (eX5) demonstrated 18% better virtual machine consolidation performance on a 40-core system versus the competition, due to more efficient virtualized I/O through the use of SR-IOV by both KVM and System x.
We also believe that the Mandatory Access Control security delivered by SELinux as part of KVM is a step above the Discretionary Access Control provided by other hypervisors. IBM and Red Hat also recently announced that KVM has achieved Common Criteria Certification with EAL4+ (for RHEL 5 with KVM on IBM System x). The Common Criteria is an internationally recognized set of standards used by governments and other organizations to assess the security and assurance of technology products.
We think KVM offers something to any environment but where KVM is being adopted especially fast is in four key segments.
First, if you already have Linux servers, because KVM is integrated already into the Linux kernel, it is a natural choice for virtualizing Linux servers, because you don’t have to do the testing and integration or purchase a separate product. KVM comes with Red Hat Enterprise Linux, SUSE Linux Enterprise Server, and Canonical Ubuntu LTS as an embedded hypervisor.
Second, we are seeing both private and public clouds use KVM because of the advantages it provides in terms of virtual machine density, low unit costs, and advanced security – such as IBM’s SmartCloud Enterprise public cloud offering.
Third, we are seeing rapid adoption of KVM in growth markets. These markets haven’t virtualized as fast as others, but are catching up very quickly and they want to have the latest and lowest cost technology in order to virtualize. There is a great deal of interest in KVM fromChina,India, and Latin American countries at the moment, as shown by the global membership of the Open Virtualization Alliance includingHuawei,China’s largest telecommunications supplier.
And last, though certainly not least, we are seeing high interest in KVM from big enterprise customers who already have a large installed base of virtualized servers using hypervisors from commercial vendors, but who are now considering other hypervisors for their next set of servers. These organizations are looking to reduce expense and this is where the low cost of KVM really comes into play — because when you are a big enterprise with a lot of virtualized servers, the total amount you are spending on virtualization escalates very quickly.
Apart from cost, the key for these big enterprise customers is: Can they manage that virtualized environment from a single pane of glass; from a systems management approach, can they manage their existing virtual machines and also the KVM machines from one console? This is where the products IBM is developing, including IBM Systems Director VMControl with its support for multiple platforms and multiple hypervisors, really help to manage existing environments.
IT managers today are looking to save money and maintain vendor independence when virtualizing their workloads - while maintaining enterprise qualities such as reliability, scalability and security. Only KVM delivers all of this and we think it’s worth a closer look – visit www.ibm.com/systems/kvm to find out more.
Jean Staten Healy
Director, WW Cross-IBM Linux and Open Virtualization