Public Cloud Vs. Bare Metal Servers: A Comprehensive Performance Benchmark Analysis

Whatever solution you choose for your business, it needs to be capable of meeting your performance needs for now and the immediate future. If you are going to invest significantly in it, then it needs to be capable of meeting your performance needs over the long term. With that in mind, here is a straightforward guide to public cloud vs bare metal performance benchmarks.

Understanding cloud vs bare metal servers

Public cloud services are typically defined as Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS), and Infrastructure-as-a-Service (IaaS). Each of these services requires management input from both the client and the public cloud service provider (CSP). The level of input on each side varies according to the service type.

With SaaS, the vendor takes responsibility for almost everything. The client just manages their own users and data. With IaaS, by contrast, the client has full control over the management of the virtualized servers. PaaS sits in between these two extremes.

Bare metal servers are often viewed as a subset of IaaS. The key difference between bare metal and regular IaaS is that bare metal servers are dedicated to a single client. This means that the client has the opportunity to customize the server’s hardware to their own specifications, however niche they might be.

Public cloud vs bare metal performance benchmarks

For many businesses, the three key performance benchmarks are latency, throughput, and computational power. That being so, here is a guide to public cloud vs bare metal performance benchmarks.

Latency

In public cloud environments, latency is often influenced by the abstraction layers introduced by virtualization. Virtual machines share the same physical resources, leading to potential contention for CPU, memory, and I/O operations. The hypervisor managing these virtual machines adds overhead, which can impact latency.

Network latency can also be affected by the cloud provider’s infrastructure, including the additional network hops and potential traffic routing through load balancers and other network devices. For instance, the introduction of Software-Defined Networking (SDN) and network virtualization can add latency due to additional packet processing and network segmentation.

Bare metal servers bypass these virtualization layers, providing direct access to the hardware. This direct access minimizes the overhead associated with virtualization and shared resource contention. Additionally, bare metal configurations often allow for optimized, high-speed network interfaces and dedicated bandwidth, reducing latency further.

For example, using Direct Memory Access (DMA) can enhance throughput and lower latency by allowing devices to access memory without CPU intervention. Moreover, bare metal servers often benefit from more consistent network performance due to fewer network hops and the ability to use high-performance, dedicated networking equipment.

Throughput

In public cloud environments, there are several factors that can potentially constrain throughput. Virtual machines (VMs) in the cloud share underlying physical resources, such as CPU and network bandwidth, which can lead to contention and reduced throughput. The network infrastructure in cloud environments often involves multiple layers, including virtual switches and routers, which introduce additional latency and can limit throughput.

Cloud providers may also enforce bandwidth caps on VMs to manage resource allocation and prevent network congestion, further impacting throughput. For example, cloud services typically use virtual network interface cards (vNICs) that are shared among multiple tenants, leading to potential bottlenecks.

Bare metal servers offer higher throughput due to their dedicated hardware and lack of virtualization overhead. With direct access to physical network interfaces and storage devices, bare metal servers can leverage high-speed, dedicated network cards and storage interfaces, which are optimized for maximum data transfer rates.

The absence of virtual switches and shared network resources means that bare metal servers can utilize the full bandwidth of their network connections, often achieving higher throughput than cloud-based counterparts. Additionally, configurable options such as multiple network interfaces and high-speed interconnects (e.g., InfiniBand) further enhance throughput capabilities.

Computational power

In public cloud environments, computational power is constrained by virtualization overhead and resource sharing. Virtual machines (VMs) share the physical server’s CPU resources, leading to potential contention and reduced performance per instance. Cloud providers use hypervisors to manage multiple VMs on a single server, which introduces additional layers of abstraction and can limit the effectiveness of CPU resources.

Additionally, cloud providers often allocate a fixed number of virtual CPUs (vCPUs) per instance, which may not fully utilize the underlying physical cores’ capabilities. Cloud environments may also apply throttling mechanisms to ensure fair resource distribution among users, impacting overall computational performance.

Bare metal servers deliver superior computational power due to their direct access to physical hardware. Without virtualization layers, applications can fully leverage the CPU’s capabilities, including all cores and threads, without the overhead introduced by hypervisors. Bare metal servers also provide the flexibility to configure high-performance CPUs with advanced features such as Turbo Boost and higher core counts.

Furthermore, these bare metal servers can be optimized for specific tasks. For example, clients can deploy processors with specialized instruction sets for data processing or scientific computing. This ensures maximum computational efficiency and performance.