To see how virtualization might play in HPC, let's consider how programs operate on a cluster. A parallel MPI program is basically a collection of individual programs (processes) running on the same or different node. Messages are essentially a way to copy memory from one program to another. Programs are "placed" on specific idle nodes/cores by a scheduling program (such as PBS, Sun Grid Engine, or Torque). The programs are managed by the all-knowing scheduler and once placed on a node, stay there until complete. Communication takes place over an interconnect, but as far as the scheduler is concerned, what you do with your nodes is your business. This model has worked well for HPC clustering although it is not the only one.
Virtualization allows the OS instance (and subsequent programs) to be run on top of a hypervisor. Because the hypervisor insulates the OS instance from the hardware it allows the OS and running programs to be migrated from one hypervisor to another.
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AS of now the results of the poll are going in this direction:
Virtualization & HPC
Will Virtualization help solve some of your HPC issue?
Would multiple/custom distribution support on the same cluster be helpful?
What is the most important capability that virtualization could bring to your HPC environment?
Would you like to learn more about Virtualization and HPC?