Book Image

vSphere High Performance Cookbook - Second Edition - Second Edition

By : Kevin Elder, Christopher Kusek, Prasenjit Sarkar
Book Image

vSphere High Performance Cookbook - Second Edition - Second Edition

By: Kevin Elder, Christopher Kusek, Prasenjit Sarkar

Overview of this book

vSphere is a mission-critical piece of software for many businesses. It is a complex tool, and incorrect design and deployment can create performance related issues that can negatively affect the business. This book is focused on solving these problems as well as providing best practices and performance-enhancing techniques. This edition is fully updated to include all the new features in version 6.5 as well as the latest tools and techniques to keep vSphere performing at its best. This book starts with interesting recipes, such as the interaction of vSphere 6.5 components with physical layers such as CPU, memory, and networking. Then we focus on DRS, resource control design, and vSphere cluster design. Next, you’ll learn about storage performance design and how it works with VMware vSphere 6.5. Moving on, you will learn about the two types of vCenter installation and the benefits of each. Lastly, the book covers performance tools that help you get the most out of your vSphere installation. By the end of this book, you will be able to identify, diagnose, and troubleshoot operational faults and critical performance issues in vSphere 6.5.
Table of Contents (17 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Choosing the best SIOC latency threshold


Storage I/O Control (SIOC) extends the constructs of shares and limits to handle storage I/O resources. SIOC is a proportional share scheduler that, under contention, throttles IOPS. You can control the amount of storage I/O that is allocated to VMs during periods of I/O congestion. Controlling storage I/O ensures that more important VMs get preference over less important VMs for I/O resource allocation.

There are two thresholds: one for standalone SIOC and one for Storage DRS. For Storage DRS, latency statistics are gathered by SIOC for an ESXi host and sent to the vCenter Server and stored in the vCenter Server database. With these statistics, Storage DRS can make the decision on whether a VM should be migrated to another datastore.

The default latency threshold of SIOC is 30 milliseconds. The default setting might be acceptable for some storage devices, but other devices might reach their latency threshold well before or after the default setting...