Virtualisation has swept the enterprise and its success has driven new innovation in hardware, software and security practices, as IT organisations demand greater performance, manageability and security from their virtualised infrastructure.
New technologies are coming to market that work at the server processor level and integrate with the hypervisor, the virtualised software system that manages and orchestrates individual virtual machines (VMs).
At the same time there is a new wave of innovation focusing on the operational efficiency of virtualised environments, with the introduction of sophisticated live migration tools, virtual network security, and software switches that sit behind the hypervisor.
Virtualisation and processors
The role of the processor in improving virtual systems performance dates back to the middle of the last decade, when chip manufacturers, Intel and AMD in particular, introduced features to make hypervisors more efficient.
They mainly accomplish this by dedicating a processor core, of a multi-core chip, to the operating system that runs the virtual environment, and this enables the VMs to run faster.
With Intel’s VT (Virtualisation Technology), for example, there is close integration between the processor and the virtualisation software – such as between Intel’s Xeon server processors and VMware’s cloud platform – which can improve performance in a virtualised environment, as well as supporting higher VM density.
At chipset level, the hardware helps to reduce the involvement of the hypervisor in managing I/O (input/output) traffic by calculating this itself, which also boosts performance.
Intel’s recently-launched Xeon E5-2600 product family incorporates Intel VT virtualisation technology, and supports up to eight cores per processor and 768GB of system memory. This combination means that Xeon E5-2600-based servers can deliver an increase in performance of up to 80% compared with servers based on the previous-generation Xeon processor 5600 series, according to Intel. Virtualised and cloud computing environments can benefit greatly from the improvement.
Intel rival AMD has its own technology called AMD-V, which incorporates virtualisation extensions in the Opteron server processor's instruction set. AMD also offers ‘Tagged TLB’: hardware features that facilitate efficient switching between VMs; and Rapid Virtualisation Indexing (RVI) which helps to accelerate the performance of certain virtualised applications by enabling hardware-based VM memory management.
Virtualisation promises data centre power efficiency savings by enabling organisations to consolidate multiple physical servers. But there are additional ways of getting efficiencies in the data centre, and some organisations are looking at using ARM chips or Intel Atom processors for small, low-power servers.
The use of these tiny chips in virtualised environments is still at the early stages, but new virtualisation options are emerging all the time.
For example, chip start-up Calxeda has produced the tiny EnergyCore ARM system-on-chip (SoC) for cloud servers. The company has put four EnergyCore chips on a board to create an ‘EnergyCard’. Five EnergyCards could support 20 OS instances in two units of rack space, creating 20 virtual servers, at a very low energy rate.
Calxeda’s EnergyCore processor also virtualises the Ethernet port, presenting Ethernet traffic to the operating system via its management engine, and this enables the efficient routing of Ethernet data and power optimisation.
SeaMicro is another manufacturer that sells a low-energy virtualisation platform. Its ‘micro-servers’ are based on Intel's Atom and Xeon CPUs. As well as virtualising both Ethernet and SATA storage ports for the sake of efficiency and motherboard size, SeaMicro has also produced technology it calls TIO (Turn It Off), with which the motherboard can switch off unused CPU and chipset functions, making the virtualised environment more efficient.
Another interesting feature of SeaMicro’s virtualisation-ready servers is that, in the case of the Atom dual-core 1.66 GHz N570 processor (the first low-power Intel Atom processor to support virtualisation), each processor supports four threads and delivers what SeaMicro calls the industry’s best performance per watt for ‘internet’ workloads. “When used on a SeaMicro motherboard, and in conjunction with SeaMicro’s power management technology, the N570 uses, at peak utilisation, less than one watt for each gigahertz of compute,” says the firm.
One of the most exciting software technologies to come to the aid of virtualised server estates is live migration for VMs, which enables a VM to be moved from one physical server to another whilst operational, without any noticeable effect from the end user's perspective.
This facilitates proactive maintenance, for example if an imminent failure is suspected, the IT department can solve the problem before services are disrupted. Live migration can also be used for load balancing, to ensure that server CPUs are used efficiently.
Forrester Research senior analyst Rick Holland said: “Technologies such as live migration help organisations harness the power of virtualisation and make the environment extremely dynamic. Today, 50% of enterprises use live migration, and 13% are planning to implement it in the next 12 months.”
Holland adds that there are many advances in virtualisation security technologies, with the ability to inspect traffic between VMs being a function worth developing. “Depending on your network architecture, virtualisation can create blind spots in your network, and many security professionals don’t have the tools to inspect intra-virtual-machine communication (traffic between two virtual machines on the same virtual server).”
Termed ‘hypervisor introspection’, this allows third-party vendors such as Bitdefender, Kaspersky Lab, McAfee, and Trend Micro to deploy a single virtual security appliance on the virtual server, which then takes over endpoint security responsibilities.
As well as improving internal security, this frees up memory and CPU resources that additional VMs can use if each one has a dedicated endpoint security agent assigned to it. The result, according to Holland, is an improvement in virtualisation efficiency.
He added: "The CTO at one highly virtualised enterprise said, ‘At 80% virtualisation, we are looking for any opportunity to increase the density and return on investment (ROI) of our virtualisation investment’."
For many IT organisations, server virtualisation is a routine part of their daily IT operations, and for others it still signifies a brave new world. But one thing is clear: as virtualised IT infrastructure becomes mainstream, there is still plenty of innovation, from both the hardware and software camps, to secure, manage and optimise virtual environments.