======Parallelizing Live Migration of Virtual Machines======

Live VM migration is one of the major primitive operations to manage 
virtualized cloud platforms. However, with the increasing amount of 
resources configured to a single VM, this process may be extremely
time-consuming, causing notable disruption to the running services.
In this project, we investigate how this process could be parallelized
on commodity multicore platforms.

=== Faculty ===

  * [[pub:members:Haibo Chen]]

=== Students ===

  * [[pub:members:Xiang Song]] [[pub:members:Jicheng Shi]] Ran Liu 　 [[pub:members:Jian Yang]]


=====Approaches=====
By leveraging abundant resources like CPU cores and
NICs in contemporary server platforms, we design and implement
a system called PMigrate that leverages data parallelism and
pipeline parallelism to parallelize the operation. 

As the parallelization
framework requires intensive mmap/munmap operations that
tax the address space management system in an operating system,
we further propose an abstraction called range lock, which improves
scalability of concurrent mutation to the address space of
an operating system (i.e., Linux) by selectively replacing the perprocess
address space lock inside kernel with dynamic and fine grained
range locks that exclude costly operations on the requesting
address range from using the per-process lock. 

=====Result=====

Evaluation with our
working prototype on Xen and KVM shows that PMigrate accelerates
the live VM migration ranging from 2.49X to 9.88X, and decreases
the downtime ranging from 1.9X to 279.89X.


=====Availability=====

The source code of this project includes three parts (each source code 
includes a README file to show how to play with PMigrate):
  - PMigrate for KVM: https://github.com/classicsong/PMigrate-KVM
  - PMigrate for Xen: https://github.com/classicsong/PMigrate-Xen
  - Range Lock Linux: https://github.com/classicsong/Range-Lock

======Publications======
   * Xiang Song, Jicheng Shi, Ran Liu, Jian Yang, Haibo Chen. Parallelizing Live Migration of Virtual Machines. In Proceedings of 2013 ACM International Conference on Virtual Execution Environments (**VEE 2013**), March, 2013. [{{:publications:parallel-migration.pdf|pdf}}]

======Acknowledgement======
This research was funded by NetApp Faculty Fellowship.