A Cloud Service Provider (CSP) offers instantaneous, scalable virtual infrastructure with utility billing. While the Cloud Infrastructure-as-a-Service (IaaS) industry streamlines IT through these advantages, a lack of standardisation in performance can lead to businesses overspending in order to obtain the necessary performance requirements for their applications.
In order to avoid this, businesses need to ensure that they have a reliable process in place for Cloud vendor selection. Assessing performance and the price-performance relationship in a holistic, industry-wide view will assist in the purchasing decision.
The price-performance relationship
Performance is a critical and often overlooked component when making a cloud purchase decision, but can have substantial impact on annual operating costs.
Why is this information necessary? A lack of transparency in the public/private cloud IaaS marketplace for performance often leads to misinformation or false assumptions. Users and potential users may be led to view cloud computing as a commodity, differentiated mostly by services. The reality of performance in cloud computing, though, impacts the user differently from CSP to CSP, involving everything from the physical hardware (e.g., Intel or AMD, SSD or spinning disk), to the cost of the virtualized resources. By identifying environments based on performance rather than resource count, users are able to maximize value in the cloud.
Misconceptions about performance in Cloud
1. VM performance is pretty much the same from CSP to CSP.
While CSPs often use the same terms to label resources (i.e., vCPUs, RAM or memory, and block storage), differences in the underlying hardware, architecture, and performance tuning lead to entirely different results from the same terms such as vCPUs. For example, on VM performance alone (the virtual processor and memory), the Top 10 IaaS providers in this report exhibited a difference of 3.4x. With block storage performance, differences exceeded 10x.
2. For performance, you get what you pay for.
When it comes to additional services such as support, security, geographical location, and managed services on CSPs, this may be true; however, regarding performance, a market study found no correlation between price and performance. The study demonstrated the best-value CSPs in this report (defined as the ratio of price and performance) offer virtualized resources at the lowest prices. Similarly sized VMs within the Top 10 IaaS providers displayed a spectrum of prices with a 5x difference between the least and most expensive CSPs.
3. Resource contention, known colloquially as the “Noisy Neighbour Effect”, is not a concern with most providers.
A public, or shared Cloud environment offers multi-tenant physical hosts, which means a business may share the same physical resources with different users on the same hardware. With a lack of understanding of other users’ activities, resource-hogging applications can affect the performance of other VMs on the host machine. While resource contention has been addressed by many of the largest providers in an attempt to stabilize VM performance, the block storage offerings still exhibit high levels of performance fluctuations, with almost a 25X difference in IOPS output, which may be related to other activity on the same physical host as Exponential-e’s test VMs. The fluctuation in performance evidenced in some CSPs can significantly affect hosted applications within those environments.
4. If the “Noisy Neighbour Effect” is a concern, then performance is too unpredictable.
In public and shared Cloud environments, some providers, especially major ones such as Google and Amazon Web Services, employ performance throttling among other strategies to deliver a consistent user experience regardless of the actual user load on the physical machine. This means that, while performance may be artificially low for the VM, the user will not see much change over time.
Key priorities and considerations
An important consideration to take away for choosing the right Cloud Service Provider (CSP) is that there is not a strong correlation between price and performance. Performance can be affected by configuration and you should address your business needs.
The number one top priority at present is no longer cloud security, but Cloud Migration. Consider a service provider who can simplify and manage the workloads, applications, strategy and contract in order to deliver on the clear business case.