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Supercharging PlanetLab : a high performance, Multi-Application, Overlay

Network Platform

Written by Jon Turner and 11 fellows.

Presented by Benjamin Chervet 8 April 2009

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Content :

• Context • Motivation• How to supercharge PlanetLab ?• Evaluation• Summary

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Context : Overlay Network ?

• Computer Network built on Top of another

• Examples– P2P Network over the Internet– Dial Up Internet over Telephone Network– PlanetLab over the Internet

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Context : PlanetLab

• Group of computers over the Internet

• Used as a testbed for research and deployment

• Shared overlay infrastructures.

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Motivations : PlanetLab limitations

• Applications run as user-space processes in virtual machines.

– Limited throughput– High, unpredictable latency

• => What is the solution ?

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Supercharging: How works a node right now ?

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Objectives of a supercharge nodes

• Better IO and processing performances

• Not too hard for users to take advantage of the modifications.

• Current PlanetLab should run on the new nodes.

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Supercharged node

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Architecture of a supercharged node

Conventional server, coordinates system

components and synchronizes with

PlanetLab

Server blade supporting standard

PlanetLab environment.

Forward the packets to correct PlanetLab

environments

Network processor supporting applications

fast-paths

Blade containing data switch and control switch.

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What is a Network processor ?

• Use of Network processor technology – A kind of processor specially designed to handle

network operations.– Programmable

– Typically used in Routers, switchs and firewalls.

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Architecture of a NP devices

• 16 Multi threaded (Mes)– Fast nearest neighbor

connections for pipelined apps.

• 3 SDRAM and 4 SRAM channels

• Management Processor for control

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NP devices

• How a NP takes advantages from multi threading ?– Cope with the memory latency gap.– Round robin

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System Control

Divided in two paths: Pink : Normal Path

Blue : Fast Path

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Using the fast path

• Process 8 packets concurrently.

• Fast path shared by slices more efficiently than the old fashion nodes.

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GPE improvements

• Use better performance hardware

• Change the scheduling of applications to improve the latency. – Number of token reduced.

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Evaluation of the improvements

• Implementation of real world applications.

– IPv4 arrive/depart in UDP tunnels.

– Internet Indirection Infrastructure (i3)

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I3

– Packets contain triggers matched to IP addresses– No match at local node results in Chord

forwarding

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IPv4 Throughput Comparison

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IPv4 Latency Comparison

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I3 Latency Comparaison

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IPv4/i3 Fast Path throughput comparison

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Summary

• Supercharged nodes remove the limitations of PlanetLab Nodes

• Easy to deploy and adapt to existing structures.

• Future work:– Automatic NPE code verification– Flexible NPE implementations