This presentation is based on http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=7164727&punumber%3D7153311%26filter%3DAND(p_IS_Number%3A7164643)%26pageNumber%3D3

1. Performance Comparison Between
Linux Containers and Virtual
Machines
Venue: 2015 International Conference
on Advances in Computer Engineering
and Applications

2. Agenda
• What is virtualization?
• Virtualization technologies
• Comparing the technologies
• Conclusion

3. What is virtualization?
• virtual machine (VM) is an emulation of a
particular computer system.
• VM is a common way to run different services in
the cloud.
• Main benefits of virtualizations are:
– Portable deployment (fast application delivery)
– Scale and deploy with ease
– Hardware independence
– Isolation
– Secure user environment
– ….

4. Virtualization technologies
• Hypervisor-based virtualization
– Kernel-based VM (KVM), VMWare
• Container-based virtualization
– Docker, LXC
• Hybrid virtualization
– ZeroVM, OSv

5. Hypervisor-based virtualization
• Operates at the hardware level
• Isolates VM from the underlying host system.
• Benefits
– Abstracts hardware
– Support running VMs independently and
isolated from the hardware (windows VM can
run on Linux host)
Problems
• A full OS runs on the VM=>
emulation of VM has huge
overhead.(big images and long
start-up time)

6. Container-based virtualization
• Implemented in Linux kernel via
– control groups(resource management)
– namespaces(restricted access to resources)
• Benefits
– A light weight alternative to hypervisor-based
– implement isolation of processes at the OS level
– Disk images are smaller
– A higher density of virtualized instances
Problems
• Window container cannot run on a Linux host
• Resource isolation is not as accurate as
hypervisors (issues for multi-tenant security)

7. Comparing the technologies-
performance comparison
• In this paper, Docker is used for running
containers.
• The set up:
– Two physical servers (OS: Ubuntu14.04, RAM: 2GB) for hosting
docker and VM.
– front-end= application server hosting Joomla
– Back-end= database server hosting Postgres
– Jmeter is used for stress testing Joomla by sending
simultaneous requests to Joomla.

8. Application performance comparison

9. Comparing the technologies-
Scalability comparison
• For container scalability test, use Kebernetes cluster manager to scale the
the Docker host on the 2 physical servers.
• For VM scalability test, The application is deployed in an AWS EC2 with
auto scaling enabled.
• The set up:
– AWS EC2 for cloud and a physical server to host docker.
– Application = a load balanced WordPress application
– Jmeter is used for stressing and trigger the scaling

10. Scalability comparison
The time to scale for deploying another container (~8
sec.) is much less than the time to scale for deploying
another virtual machine (~3 mins).
=> 22x times faster scalability

11. Conclusion
• Containers out performed virtual machines
both in terms of scalability and performance.
• Containers are better for application
deployment.
• However, using containers for applications
with business critical data may reveal security
breaches.