Book Image

Mastering KVM Virtualization

Book Image

Mastering KVM Virtualization

Overview of this book

A robust datacenter is essential for any organization – but you don’t want to waste resources. With KVM you can virtualize your datacenter, transforming a Linux operating system into a powerful hypervisor that allows you to manage multiple OS with minimal fuss. This book doesn’t just show you how to virtualize with KVM – it shows you how to do it well. Written to make you an expert on KVM, you’ll learn to manage the three essential pillars of scalability, performance and security – as well as some useful integrations with cloud services such as OpenStack. From the fundamentals of setting up a standalone KVM virtualization platform, and the best tools to harness it effectively, including virt-manager, and kimchi-project, everything you do is built around making KVM work for you in the real-world, helping you to interact and customize it as you need it. With further guidance on performance optimization for Microsoft Windows and RHEL virtual machines, as well as proven strategies for backup and disaster recovery, you’ll can be confident that your virtualized data center is working for your organization – not hampering it. Finally, the book will empower you to unlock the full potential of cloud through KVM. Migrating your physical machines to the cloud can be challenging, but once you’ve mastered KVM, it’s a little easie.
Table of Contents (22 chapters)
Mastering KVM Virtualization
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

CPU tuning


I would like to reiterate that vCPUs are POSIX threads in the KVM host. You can allocate vCPUs for guest systems according to your needs. However, to get the maximum or optimal performance, it is always better to allocate required virtual CPUs for each guest based on the expected load of the guest operating system. There is nothing wrong with allocating more than is needed; however, it may cause scaling issues in future, when considering the host system as a single unit serving all configured guests.

There is also a misconception that the number of vCPUs defined by all of the guest systems should be less than the total number of CPUs available in the HOST system. To expand further on this thought, if the total number of CPUs available in the HOST system is 32, some people think they can only define eight vCPUs each if they defined four guests in the system. There is no rule like that. Generally speaking, these vCPUs are lightweight processes running in your KVM hosts that get...