DistOS 2014W Midterm Review

From Soma-notes

Themes

  • Scaling
  • caching
  • consistency
  • specialized versus general solutions
  • OS abstractions
  • paths not taken
  • network transparency (making remote look like local)
  • reliability
    • fault tolerance
    • redundancy
    • availability
  • resource sharing
  • information sharing
  • communication
  • collaboration
  • peer-to-peer versus hierarchy
  • latency versus bandwidth

Questions

  • The architecture of distributed OSs typically are some mix of peer-to-peer and hierarchies (e.g. master/slave) in the arrangement of servers. Give an example of each and explain why the choice was made (a hierarchy versus peer-to-peer).
  • "UNIX compatibility is increasingly sacrificed in order to improve scalability." Argue for or against.
  • Ceph is the solution to what problem? How does it solve that problem? (Choose at least one problem to discuss.)
  • Describe three strategies used to increase scalability in distributed operating systems. Give and explain specific examples of each.
  • What is a distributed operating system? Does a distributed operating system exist (at Internet scale)? Explain.
  • Describe three data consistency models that have been used in the systems we have discussed in class. Why are there different ones, and what are the trade-offs? Give at least one example of each.
  • Describe three ways (tasks/use cases) that computers were envisioned to be used in the Mother of All Demos. For each, how are these use cases addressed in current systems? Does current usage fit within Englebart's vision?