Supercharging PlanetLab

1. A High Performance,Multi-Alpplication,Overlay Network Platform Supercharging PlanetLab Reviewed by YoungSoo Lee CSL

2. Overview • PlanetLab has become a popular experimental platform. • But PlanetLab are subject to high latency, high delay jitter, poor performance. What is the Solution?

3. Solution

4. SSP’s Objectives • Higher level of both IO performance and processing performance. • Reasonably straightforward for PlanetLab users take advantage of the capabilities • Require t.hat legacy PlanetLab applications run on the system without change.

5. System Overview • Modern NPs are not designed to be shared. • Application are divided into Fast Path and Slow Path

6. System Components • Line Card(LC) : LC forwards each arriving packet to the system component, and queues outgoing packets for transmission. • General Purpose Processing Engines(GPE). • Network Processing Engines(NPE) • Control Processor(CP)

7. Network Processor Issues • NP products have been developed for use in conventional router. • Micro-Engines(ME) : packet processing. • DRAM : packet buffer. • SRAM : implementing lookup table & linked list queues. • MP : overall system control

8. Network Processor Issues • NP provides a different mechanism for coping with the memory latency gap, hardware multithreading. • Operate in a round-robin fashion.

9. Sharing the NPE • Develop software for the NPE that allows it to be shared by the fast path segments of many different slices. • Process 8 packets concurrently using the hardware thread contexts.

10. Sharing the NPE • Rx : packet received from switch are copied to DRAM & passes a pointer main packet processing pipeline. • Substr. : determines which slice the packet belongs & strips outer header form the packet. • Parse : preconfigured set of Code Option & form lookup key.

11. Sharing the NPE • Lookup : provides generic lookup capability. • Hdr Format : makes necessary changes to the slice-specific packet header. • Queue Manager : implements a configurable collection of queues. • Tx : forwards the packet to the output.

12. Enhancing GPE Performance • Boost performance of the GPEs. • 1. Use higher performance hardware configurations than usual for PlanetLab. • 2. Improve the latency of PlanetLab applications. • Changing coarse-grained scheduling paradigm

13. Enhancing GPE Performance

14. Enhancing GPE Performance

15. Overall System

16. Slice Configuration • ① : CP obtains slice configuration data using the standard PlanetLab mechanism of periodically polling the PLC • ② : Slices are assigned to one of GPE by GNM. • ③ : Corresponding entry is made in a local copy of my PLC. • ④ : The LNM on each of the GPEs periodically poll myPLC to obtain new slice configurations. ④ ① ② ③

17. Port Assignment • ① : LRM reservation request th the GRM. • ② : If the requested port number is available, it makes the appropriate assignment to LRM. • ③ : GRM configures the Line Card so that LC will forward to the right GPE. ① ③ ②

18. NPE Assignment • ① : LRM forwards the request to the GRM. • ② : GRM selects the most appropriate NPE to host the slice and returns its id to the LRM • ③ : LRM then interacts with the MP. ① ② ③

19. Evaluation • Implement two different application. • IPv4 & Internet Indirection Infrastructure.

20. IPv4-Fair Queueing Mechanism

21. IPv4-Fair Queueing Mechanism

22. IPv4 - Throughput

23. IPv4 - Latency

24. Internet Indirection Infrastructure

25. IPv4 & III- Throughput

26. III- GPE vs NPE