ProportionalEnsemble Discussion Summary

[Matt Mallozzi]

Sorry for the delay:

The viability of virtual machines (and migrating them) for distributed systems

applications

  - Migrating (at least blindly) is probably not a good idea for systems that

    are supposed to be fault tolerant, because if your n replicas of your

    data/service are on fewer than n physical machines, a small number of node

    failures could take down the entire system.

  - The migration itself is fairly feasible with respect to performance when

    done inside a data center, as computation does not need to freeze while

    the gigabytes worth of VM state is copied over the network.

  - Migration is probably not feasible on an Internet scale.

Other approaches to power saving

  - Fix the hardware

  - Build your data centers in Alaska

The optimization problem

  - Is a simple bin packing problem (minimize the number of physical nodes while

    meeting capacity constraints on the amount of CPU power and memory a

    physical node has) enough to express the relevant complexities, or would a

    more descriptive (and thus more difficult to solve) formulation provide a

    noticeable difference?