This document summarizes a presentation given at the Xen Summit 2008 in Tokyo about challenges in managing large virtualized environments. The presentation discussed scaling a machine pool from 10 to 1,000 physical machines and how different challenges arise at each level, including hardware compatibility and automation. It also covered different types of virtual machines for servers, desktops, and labs and how to integrate them. Finally, it provided an overview of how Google uses Ganeti to manage its virtualized infrastructure by fully automating resource management across a large cluster of machines with varying hardware over time.
3. Introduction
Use cases of virtualization:
•traditional:
improved resource utilization
consolidate lowusage machines
•but the technology has matured:
focus moves to higher layers (management)
large numbers of both physical and virtual machine
more uses (VM types)
Disclaimer:
•the presentation content is not representative of Google's usage of
virtualization
•the presentation solely refers to the use of virtualization in Google for internal,
corporate purposes and not external services or products (e.g.
www.google.com)
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Copyright by Google Inc
4. Abstract model
app app app app app
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hypervisor
resource mgmt.
base OS base OS
hardware layer
hardware hardware
multiple app
single-app or virtualized
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Copyright by Google Inc
7. Up to 100 physical machines
Similar to nonvirtualized environments:
•component failure is rare, but part of normal life
•automation benefits start to show (deployment, configuration, etc)
Specific to virtual environments:
•diverse configurations and machine mobility mean VMs will be shifted around
and their HW profile can change dynamically
•cost savings are split between resource utilization and operational gains
Challenges:
•accommodating various customer types
•integration of VM and nonVM environments
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8. Up to 1,000 physical machines
Number of machines affect cost profile:
•HW costs are linear, but operations costs no longer
•Automation and standardization across all layers have big benefits
the hypervisor and HW layers can be deeply abstracted by the management tools
automation of all procedures is paramount to keeping the VM environment healthy
Challenges:
•multiple customers, same management toolset
•software upgrades for physical machines
•dealing with multiple HW generations
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Copyright by Google Inc