Mesh Testing

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This page describes the network testing that will be performed on Monday Feb 25th at 1cc.

Setup:

  • Start with ten machines, keep adding ten at a time while it is useful to do so.

Measurements to make during each test (in addition to workload-specific measurements):

  • Spectrum utilization -- as measured w/ spectrum analyzer and/or from wireshark
    • Wireshark may be able to break down bandwidth by packet type
  • Remaining bandwidth -- attempt to download a large file on one machine during test, record time taken or bandwidth achieved.
  • Total # of laptops seen on mesh view on all numbers (should be n^2).

Workloads -- tests to perform, along with their quantitative metrics:

  1. Idle load.
  2. Every machine coming out of suspend (or booting).
  3. Every machine trying to register with school server -- Number of machines that failed the first attempt, failed second attempt, etc.
  4. Ricardo's web spider at various rates of download (download 1k page/second, etc)
  5. Read -- if one laptop shares a PDF, how many laptops fail to retrieve it?
  6. Distance -- binary success/fail. Are there other metrics?
  7. Write -- automate pressing N characters a second for small N, look at received rate/update time, increase number of participants per document.
  8. olpc-update -- number of machines upgraded in 1 hour

Variables to investigate:

  • Set mesh ttl to 1 for every packet
  • Change bcast/mcast rate on every node
  • Jim's Avahi config 30% fixes?
  • Presence: Benchmark bandwidth use of Avahi vs. Cerebro vs. no presence?
  • Collaboration: Benchmark switching from multicast to unicast?
  • Suspend/resume: Off vs. on, wake-on-unicast vs. wake-on-multicast
  • Block multicast in route table (are there other sources of multicast packets other than the above?)
  • Are there other mesh parameters to tweak? Path request timeout, for example.