Best Practices for Virtualization: Optimizing Host and Guest Machines

Welcome to our blog series on best practices for virtualization. In this series, we will delve into essential guidelines for maximizing performance and efficiency in both your virtualization host and guest machines. By following these best practices, you can ensure a smooth and optimized virtualization environment. We will cover a range of topics, including general BIOS settings, considerations for optimal performance, memory management, CPU utilization, and more. In the upcoming articles, we will explore storage considerations to further enhance your virtualization setup.

Virtualization has become a vital technology in modern computing environments, enabling efficient resource utilization and flexible management of virtual machines (VMs). However, to make the most of virtualization, it’s important to adhere to best practices that promote stability, security, and performance across the entire infrastructure.

In this blog series, we will provide you with a comprehensive checklist of best practices for virtualization. We will start by discussing general BIOS settings that can optimize the host machine’s performance and compatibility with virtualization technologies. Understanding and configuring these settings correctly is crucial for creating a solid foundation for your virtual environment.

Next, we will explore various considerations to keep in mind when setting up and managing virtual machines as guests on the host. We will delve into memory management techniques to ensure efficient allocation and utilization of system resources. Additionally, we will cover CPU considerations, including the activation of features like hyper-threading and Turbo Boost, which can significantly enhance performance.

Throughout the series, we will explain why each practice is important and how it contributes to the overall success of your virtualization setup. By following these guidelines, you can improve the reliability, scalability, and efficiency of your virtual infrastructure.

Checklist

General BIOS Setting

• Latest version of BIOS.

• BIOS must be set to activate all populated processor sockets and to activate all cores in each socket.

• Activate “Turbo Boost”.
  • It allows the processor to dynamically increase it’s clock speed to deliver high performance when needed. Enabling this processor intelligently identifies when additional performance is required and adjusts its clock speed.

• Make sure hyperthreading is activated in bios settings.
  • It allows a single physical processor core to behave as two logical cores.

• Activate all hardware assisted virtualization features.

• Deactivate unused devices.

• Leave memory scrubbing rate to manufacturer’s default.
  • Memory scrubbing is a method to detect and correct errors in memory, specifically in RAM. It involves periodically reading and verifying the integrity of data stored in memory to identify and rectify any errors.

• If the BIOS supports AES-NI, then activate it.
  • It provides hardware-accelerated support for encryption and decryption operations using the AES algorithm. With AES-NI enabled, the CPU can offload the AES encryption and decryption computations to dedicated hardware circuits

General Considerations

• Allocate how much is required. Provisioning more resources in some cases reduce the performance of that virtual machine.

• Deactivate or disconnect unused hardwares like: COM ports, LPT ports, USB controllers, CD or DVD drives, Network interfaces, storage controllers.

• Deactivate unused virtual hardwares.

CPU Considerations

• Periodically monitor the CPU usage of the host using esxtop or resxtop or vsphere client. If the load average on the first line of esxtop CPU panel is equal or greater than 1, this indicates that the system is overloaded.

• Configuring a virtual machine with more virtual CPUs that its workload can use might cause slightly increased resource usage, potentially impacting performance on very highly loaded systems. Unused vCPUs still consumes timer interrupts in some guest operating system

Side Channel Vulnerability: Information leakage between virtual machine when hyper-threading is activated.

Memory Considerations

• Memory sizing:
  • Allocate enough memory to hold the working set of applications you will run in the virtual machine to minimize thrashing. constantly moving data between physical memory and secondary storage to free up space for other data.
  • Don’t allocate too much than needed
  • If you choose to overcommit memory, be sure you have sufficient swap space on your ESXi system.
  • You can also configure a special host cache on an SSD to be used for the swap to host-cache feature.

Stay tuned!

Stay tuned for the upcoming articles, where we will delve into storage considerations. We will explore strategies for efficient storage management, including disk commands, file system choices, and optimizing storage performance for virtual machines.

Join us on this journey to uncover the best practices for virtualization and unlock the full potential of your virtual environment.

Our other loved articles:

• https://secnep.com/setup-ansible-in-your-servers/

• https://secnep.com/deploying-a-server-basic-configurations-for-ubuntu/

• https://secnep.com/deploying-a-server-part-2/