1 / 27

DRR Slide Show

DRR Slide Show. DRR Example:. Quantum = 50. deficit counters. queues. 40. 40. 10. 30. 0. 20. 30. 10. 45. 0. 40. 10. 20. 20. 0. 40. 40. 20. 35. 0. DRR Example:. Quantum = 50. deficit counters. queues. 40. 40. 10. 30. 50. 20. 30. 10. 45. 0. 40. 10. 20. 20.

steve
Download Presentation

DRR Slide Show

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. DRR Slide Show

  2. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 0 20 30 10 45 0 40 10 20 20 0 40 40 20 35 0

  3. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 50 20 30 10 45 0 40 10 20 20 0 40 40 20 35 0

  4. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 20 20 30 10 45 0 40 10 20 20 0 40 40 20 35 0

  5. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 0 40 10 20 20 0 40 40 20 35 0

  6. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 50 40 10 20 20 0 40 40 20 35 0

  7. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 0 40 40 20 35 0

  8. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 50 40 40 20 35 0

  9. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 30 40 40 20 35 0

  10. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 10 40 40 20 35 0

  11. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 0 40 40 20 35 0

  12. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 10 40 40 20 35 50

  13. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 10 20 30 10 45 5 40 10 20 20 10 40 40 20 35 15 Note that we have completed one round. Observation: no flow has enough quota to send another message.

  14. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 60 20 30 10 45 5 40 10 20 20 10 40 40 20 35 15

  15. DRR Example: Quantum = 50 deficit counters queues 40 40 10 30 20 20 30 10 45 5 40 10 20 20 10 40 40 20 35 15

  16. Back to Presentation

  17. dDRR Slide Show

  18. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 50 0 20 30 10 45 50 0 40 10 20 20 50 0 40 40 20 35 50 0

  19. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 50 0 20 30 10 45 50 0 40 10 20 20 50 0 40 40 20 35 50 0 setup: request = 45 < deficit counter = 50 suspension flag not set decision: grant

  20. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 50 0 20 30 10 0 50 0 40 10 20 20 50 0 40 40 20 35 50 0 If previous setup was blocked: teardown ack 0, so do not subtract from deficit counter

  21. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 50 0 20 30 10 45 5 0 40 10 20 20 50 0 40 40 20 35 50 0 If previous setup was successful: teardown ack 45, so subtract 45 from deficit counter

  22. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 50 0 20 30 10 45 5 0 40 10 20 20 50 0 40 40 20 35 50 0 Next request wants 10, but 10 > deficit counter...

  23. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 50 0 20 30 10 45 55 1 40 10 20 20 50 0 40 40 20 35 50 0 Next request wants 10, but 10 > deficit counter… so block, set suspension flag and (pre)increase deficit coutner.

  24. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 60 1 20 30 10 45 55 1 40 10 20 20 50 1 40 40 20 35 65 1 Eventually, all flows would have exhausted the original 50 units assigned to their deficit counters… Observe that all suspension flags are set. Start a new round.

  25. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 60 0 20 30 10 45 55 0 40 10 20 20 50 0 40 40 20 35 65 0 Starting a new round: Clear all suspension flags.

  26. dDRR Example: Quantum = 50 deficit counters suspension flag queues 40 40 10 30 60 0 20 30 10 45 55 0 40 10 20 20 50 0 40 40 20 35 65 0 request = 10 < deficit counter = 55, suspension flag is unset, decision: grant

  27. Back to Presentation

More Related